The American Board of Internal Medicine (ABIM) is the nonprofit physician-led organization that certifies internists and internal medicine subspecialists in the United States. Founded in 1936 and headquartered in Philadelphia, ABIM has issued more than 280,000 active certifications across internal medicine and 20 subspecialty disciplines, making it one of the largest member boards of the American Board of Medical Specialties (ABMS).
For an internist, ABIM certification is more than a piece of paper. Hospital privileges, insurance panel acceptance, malpractice underwriting, fellowship eligibility, and patient trust all hinge on whether a physician is board-certified by ABIM. Roughly 88% of practicing internists in the United States hold ABIM certification, and that share rises above 95% in major academic health systems and large multispecialty groups.
This guide explains exactly what ABIM is, what it does, how the certification process works from residency to lifetime maintenance, what the Internal Medicine Certification Exam looks like in 2026, how the new Longitudinal Knowledge Assessment (LKA) is replacing the traditional 10-year recertification exam, current fees, pass rates, the 20 subspecialty certifications ABIM grants, how patients and employers can verify a physician's status, and the ongoing controversies around Maintenance of Certification (MOC) costs and value.
Whether you are a PGY-3 about to register for your first board exam, an attending choosing between LKA and the long exam, or a credentialing coordinator confirming an applicant's status, this guide covers the full picture.
Before diving in, if you are still earlier in the pathway, review our what is internal medicine overview and the internal medicine residency programs guide so the certification timeline below makes sense in context.
ABIM is a private, nonprofit, physician-led certifying board incorporated in 1936. Its mission, in plain language, is to set the standard for what it means to be a competent internist. ABIM does not license physicians (state medical boards handle licensure) and does not accredit residency programs (the ACGME handles that). ABIM certifies individual physicians, attesting that they have completed accredited training and demonstrated the medical knowledge expected of an internist or subspecialist.
The board has roughly 200 staff and is governed by a Board of Directors plus subspecialty boards that include practicing physicians, medical educators, and public members. Its operations are funded almost entirely through certification and MOC fees paid by physicians. ABIM is not part of the federal government, the AMA, or any insurance company, although its certification status is recognized by all 50 state medical boards, every major commercial payer, and the Centers for Medicare & Medicaid Services for various quality programs.
ABIM is a member of the American Board of Medical Specialties (ABMS), a federation of 24 specialty boards that collectively set US physician certification standards. ABIM is the largest of the 24, certifying more physicians than any other ABMS member. Its certifications also feed into hospital quality reporting (Leapfrog, US News & World Report) and patient-facing physician finders run by health systems and insurers.
Three core functions drive everything ABIM does: setting the standard, certifying physicians, and maintaining certification over a career. Initial certification involves writing exam content, scoring it, and granting the Diplomate credential after a candidate passes.
Maintenance of Certification (MOC) is the lifelong process by which Diplomates demonstrate they remain current — through continuing education, the LKA or 10-year exam, and periodic attestation of licensure and professional standing. ABIM also performs subspecialty certification, runs the In-Training Examination (ITE) used by residency programs, and publishes the public verification tool patients and employers rely on. Each function is examined in detail later in this guide.
To earn initial ABIM certification in internal medicine, a physician must (1) graduate from an LCME-accredited MD or COCA-accredited DO program (or an ECFMG-certified international medical school), (2) complete a 3-year ACGME-accredited internal medicine residency, (3) demonstrate satisfactory clinical competence as attested by the program director, and (4) pass the ABIM Internal Medicine Certification Examination. The exam is offered each August and September at Pearson VUE testing centers nationwide. Once a candidate passes, they receive the Diplomate credential and are listed in ABIM's public verification database as board-certified.
MOC is the ongoing process Diplomates use to keep certification active. Every 2 years, Diplomates must complete some MOC activity; every 5 years, they must accumulate 100 MOC points across three categories — medical knowledge, practice assessment, and patient safety. Diplomates also attest annually to active, unrestricted licensure and good standing. MOC points come from CME, board-approved self-assessment modules, quality improvement projects, and other activities. The annual MOC program fee is approximately $220 per certificate.
Launched in 2022, the LKA is ABIM's new ongoing knowledge assessment that replaces the traditional 10-year recertification exam for Diplomates who opt in. Instead of one high-stakes 10-hour exam every decade, Diplomates answer 30 questions per quarter over 5 years (600 questions total). Each question allows up to 4 minutes, and Diplomates can use any online resource (UpToDate, journals, drug references). The LKA passes a Diplomate as long as they meet performance thresholds across the 5-year cycle. Most internists certified after 2022 are choosing LKA.
ABIM operates a free public verification tool at abim.org/verify-physician. Anyone — patients, hospitals, insurers, employers — can search by physician name and state to confirm board certification status, certification date, subspecialty certifications, and whether MOC is current. The tool returns one of three statuses: Certified (current), Not Certified (never certified or lapsed), or Certified, Not Meeting MOC Requirements (passed initial exam but MOC has lapsed). The tool is the gold standard for credentialing and patient-facing physician finders.
The path from medical school graduate to board-certified internist is a structured, multi-year sequence. ABIM does not issue certification at any point during medical school or residency; certification is only awarded after a candidate has completed accredited training and passed the formal Certification Examination. The full sequence usually spans 7-8 years from the start of medical school for US MD/DO graduates, longer for international medical graduates who need additional clinical experience.
Three years of categorical internal medicine residency in an ACGME-accredited program is the bedrock requirement. The program director must attest that the candidate has demonstrated satisfactory clinical competence across all six ACGME core competencies — patient care, medical knowledge, practice-based learning, interpersonal communication, professionalism, and systems-based practice. Med-Peds residents complete a combined 4-year program and may sit for both ABIM and ABP. Research and physician-scientist track residents may use the ABIM Research Pathway, which compresses residency and fellowship and reduces total training by 6-12 months.
Candidates register through the ABIM Candidate Portal at abim.org during the spring of PGY-3. Registration requires payment of the $1,375 exam fee, electronic attestation of pending residency completion, and consent to ABIM's policies. A late registration window opens for an additional $400 fee. Candidates whose program directors do not return their attestation by mid-summer cannot sit for the August-September exam window and must wait a full year — a costly delay that occasionally trips up residents in unfamiliar programs.
The exam is delivered at Pearson VUE testing centers across the United States. Once a candidate passes, ABIM publishes their name as a Diplomate in the public verification database, typically within 6-8 weeks of the exam window closing. From that point, MOC obligations begin. Pass rates for first-time US MD/DO graduates hover around 88-90%; IMG first-time pass rates run roughly 70-75%, with significant variation by country of medical education and time elapsed since graduation.
Diplomate status is not permanent without ongoing effort. Failure to maintain MOC (whether through LKA, the 10-year exam, points, attestation, or fees) results in the verification status changing to Certified, Not Meeting MOC Requirements. Hospital credentialing committees and many insurers treat that status as functionally equivalent to lapsed certification.
Complete LCME-accredited MD, COCA-accredited DO, or ECFMG-certified international medical degree. Pass USMLE Step 1 (pass/fail since January 2022), Step 2 CK, and Step 3 (typically during PGY-1 or PGY-2).
Begin July 1 after Match Day. Heavy inpatient wards, ICU, night float. Take the ABIM In-Training Examination (ITE) in October. Continue Step 3 prep.
Increased autonomy on wards and consults. Take ITE again in October. Apply to fellowship in summer of PGY-2 if pursuing subspecialty training.
Register for the ABIM Internal Medicine Certification Exam by deadline (typically May 1). Program director files attestation in summer. Begin focused board prep — most candidates start 4-6 months out.
Sit for the ABIM exam at a Pearson VUE testing center. The exam is 10 hours, 240 multiple-choice questions in 4 blocks. Results released 6-8 weeks later.
Pass result triggers publication on the ABIM verification database. Certificate mailed within 8-12 weeks. Diplomate status active for 10 years (traditional pathway) or rolling with LKA.
Attest to active licensure annually. Begin earning MOC points (100 over 5 years). Start LKA quarterly questions OR plan for 10-year exam.
Verify 100 MOC points earned across knowledge, practice assessment, and patient safety. Confirm LKA quarter completion is on track if enrolled in LKA pathway.
Diplomates not on LKA must pass the 10-year recertification exam. LKA Diplomates simply continue the rolling assessment — no high-stakes exam day required.
The ABIM Internal Medicine Certification Examination is a one-day, computer-based, multiple-choice exam delivered at Pearson VUE testing centers across the United States during a 4-week window each August through September. The total testing time is 10 hours, broken into four 2-hour blocks of 60 questions each, plus 2 hours of optional breaks. Most candidates use breaks for restroom, hydration, and mental reset between blocks rather than studying.
All 240 questions are single-best-answer multiple choice with 4-5 options each. There are no free-response, image-only, or essay questions. Roughly 75% of questions present a clinical vignette (patient age, presenting complaint, vital signs, labs, imaging), and the candidate must identify the most likely diagnosis, next best step in management, or most appropriate test. The remaining 25% test direct medical knowledge and clinical decision-making at the practicing-internist level.
Content blueprint as of 2026: Cardiovascular Disease (14%), Gastroenterology (9%), Pulmonary Disease (10%), Infectious Disease (9%), Endocrinology/Metabolism (9%), Rheumatology/Orthopedics (8%), Hematology (6%), Oncology (6%), Nephrology/Urology (6%), Neurology (4%), Allergy/Immunology (3%), Dermatology (3%), Obstetrics/Gynecology (3%), Psychiatry (4%), Ophthalmology/Otolaryngology (1%), and General Internal Medicine including geriatrics, palliative care, ethics, and biostatistics (5%). High-yield study should prioritize the largest content blocks first.
ABIM reports pass rates publicly each year. For first-time US MD/DO graduates of ACGME-accredited residencies, pass rates have ranged 88-92% in recent years. For IMGs, first-time pass rates run 70-75%. Repeat takers (those who failed and re-sit) pass at lower rates, typically 50-65%, because question content rotates and time pressure compounds. Scores are reported as a 3-digit scaled score with a passing standard around 366 (criterion-referenced — the standard does not curve based on cohort performance).
For deeper prep, see our internal medicine board exam preparation guide, which covers study schedules, question banks, and the highest-yield resources, and try our internal medicine exam practice question banks.
Beyond general internal medicine, ABIM certifies physicians in 20 subspecialties. To earn a subspecialty certificate, a Diplomate must first hold initial IM certification, then complete an ACGME-accredited fellowship in the chosen subspecialty, and then pass that subspecialty's certification exam. The exam format mirrors the IM exam — one day, 4 blocks, multiple choice, scored against a criterion-referenced standard.
The 20 ABIM subspecialty certifications are: Adolescent Medicine, Adult Congenital Heart Disease, Advanced Heart Failure and Transplant Cardiology, Cardiovascular Disease (Cardiology), Clinical Cardiac Electrophysiology, Critical Care Medicine, Endocrinology, Diabetes and Metabolism, Gastroenterology, Geriatric Medicine, Hematology, Hospice and Palliative Medicine, Infectious Disease, Interventional Cardiology, Medical Oncology, Nephrology, Pulmonary Disease, Pulmonary Disease and Critical Care Medicine (combined), Rheumatology, Sleep Medicine, Sports Medicine, and Transplant Hepatology.
Diplomates can also earn the Focused Practice in Hospital Medicine (FPHM) designation — a Hospitalist-specific MOC pathway introduced in 2010 that allows internists practicing primarily in inpatient settings to demonstrate hospital-focused competence without completing a separate fellowship. FPHM is not a subspecialty per se but a recognized practice focus within the MOC framework.
Cardiology, gastroenterology, and hematology-oncology consistently top the competitiveness rankings. Cardiology in particular fills nearly every year through the NRMP Medicine Specialty Match, with applicants needing top-tier IM residency placement, strong ABIM ITE scores, peer-reviewed publications, and senior faculty letters. Geriatrics, infectious disease, nephrology, and endocrinology have shown lower fill rates in recent matches, sometimes leaving 20-30% of fellowship spots unfilled — partly a function of lower compensation relative to procedural subspecialties.
MOC is ABIM's framework for ongoing demonstration of competence. There are three pillars: medical knowledge, practice assessment (quality improvement), and patient safety. Every Diplomate must earn 100 MOC points every 5 years across these three areas, with at least some points in each category. Points are earned through CME activities tagged as MOC-eligible, ABIM-approved self-assessment modules (Knowledge Check-Ins), quality improvement projects, and other approved activities.
The three categories are weighted roughly equally. Medical knowledge points come from CME, MKSAP modules (Medical Knowledge Self-Assessment Program from the American College of Physicians), board review courses, and journal-based learning. Practice assessment points come from QI projects, chart audits, patient experience surveys, and registry participation. Patient safety points come from completing patient safety modules (often free or low-cost online courses on topics like medication reconciliation, fall prevention, and hand hygiene). Many internists earn most points through the MOC-eligible CME they already complete for state licensure.
Beyond points, Diplomates must attest annually that they hold an active, unrestricted medical license in at least one US jurisdiction and that they have no professional standing issues (felony convictions, license suspensions, hospital privilege revocations). The attestation is brief — a few minutes through the ABIM portal — but missing it triggers MOC-not-met status within 90 days.
If a Diplomate fails to meet MOC requirements, their public verification status changes to Certified, Not Meeting MOC Requirements. The Diplomate technically remains board-certified (the underlying credential never disappears), but most credentialing committees and insurance panels treat the new status as functionally equivalent to lapsed. Hospital privileges, insurance contracts, and patient-facing physician finders all flag MOC-not-met. Restoring full status requires catching up on missed activities, paying back fees, and in some cases completing a remediation exam.
ABIM's public verification tool is the gold standard for confirming an internist's certification status. The tool is free, requires no login, and is available at abim.org/verify-physician. Search by physician first and last name plus state of practice. Results return the physician's primary IM certification status, any subspecialty certifications, the certification date, and MOC compliance status.
The tool returns one of three statuses. Certified means the physician has passed initial certification, is meeting all MOC requirements, and holds active certification in good standing. Certified, Not Meeting MOC Requirements means the physician passed initial certification but is currently behind on MOC points, attestation, or fees. Not Certified means either the physician never passed certification or their certification lapsed years ago and was never restored. A small number of physicians appear as Certified, MOC Pending during catch-up periods.
Hospital credentialing committees verify every new applicant against the ABIM database before granting privileges. Insurance panel coordinators verify before contracting. Patient-facing physician finders run by health systems and insurers pull live ABIM data to display certification badges. Patients themselves can verify their internist's status before scheduling — particularly useful when choosing a primary care physician or considering whether to switch internists. Use our internal medicine near me guide to find a verified internist in your area.
Many patients and even some employers confuse board-certified with board-eligible. The distinction matters and is increasingly enforced by insurance contracting and hospital credentialing.
A board-certified internist has completed accredited residency training, passed the ABIM Internal Medicine Certification Exam, and is meeting all MOC requirements. They appear in the ABIM verification database with Certified status. Most US hospitals require board certification (or active progress toward it) for medical staff privileges, and most insurance panels require board certification for in-network contracting.
A board-eligible internist has completed accredited residency training but has not yet taken or passed the ABIM exam. They are legally licensed to practice medicine (state medical boards grant licenses, not certifying boards), but they do not hold ABIM certification. Many hospitals grant time-limited board-eligible status — typically 5-7 years from residency graduation — during which the physician must pass the exam or lose privileges. Board-eligible physicians can be excellent clinicians, but insurance panels, malpractice insurers, and patient finders flag the difference.
Hospital quality reporting, US News & World Report rankings, and Leapfrog hospital safety scores all use board-certification rates as a quality indicator. Insurance panels often pay board-certified physicians at higher contracted rates. Malpractice premiums are typically 10-25% lower for board-certified internists. Patients increasingly check certification status before choosing a doctor, and physician-finder tools display certification badges prominently. For an internist, the time and cost of board certification pays back many times over the course of a career.
Every IM resident takes the ABIM In-Training Examination annually in October. The ITE is a 4-section multiple-choice exam designed to predict performance on the eventual ABIM Internal Medicine Certification Exam. ITE scores are reported as percentiles relative to PGY-1, PGY-2, and PGY-3 residents nationally, plus a 3-digit equated score that maps to the certification exam scale.
The PGY-3 ITE is the single best predictor of first-time certification exam passage. Residents who score below the 35th percentile on the PGY-3 ITE pass the certification exam at first attempt at approximately 70%, compared to 95%+ for residents above the 50th percentile. Programs use the PGY-3 ITE as a remediation trigger — residents below the threshold often receive structured study plans, paired faculty mentorship, additional protected board prep time, and required question-bank completion before sitting for the certification exam. Read our internal medicine ite exam guide for full ITE prep and scoring details.
IMGs follow the same ABIM certification process as US graduates with two added requirements. First, ECFMG certification is required — graduates of non-LCME-accredited international medical schools must pass USMLE Step 1, Step 2 CK, Step 2 CS (until its retirement in 2021) or its replacement OET pathway, and obtain ECFMG certification before matching into ACGME residency.
Second, IMGs entering residency on a J-1 visa must complete a 2-year home residency or obtain a J-1 waiver after training to remain in the United States. Once in ACGME residency, IMGs follow the identical 3-year IM curriculum, sit the same ITE, and take the same ABIM certification exam.
The Research Pathway is a structured pathway for physician-scientists that compresses residency and fellowship training by 6-12 months. Candidates complete 24 months of clinical IM training, then transition directly to subspecialty fellowship with significant dedicated research time. The pathway is highly competitive and typically requires MD/PhD credentials, sustained research productivity (publications, grants), and program-director endorsement. Total time from MD to subspecialty board eligibility drops from the standard 7 years to 5-6 years.
Military residency programs at Walter Reed, San Antonio Military Medical Center, Naval Medical Center San Diego, and other military medical centers are ACGME-accredited and produce board-eligible internists on the same timeline as civilian programs. Military residents earn the same Diplomate credential after passing the certification exam. Service obligations typically extend 3-4 years post-residency, often counting toward HPSP scholarship payback.
Registration opens through the ABIM Candidate Portal at abim.org each spring, with primary registration closing around May 1. Candidates pay the $1,375 fee, designate their preferred testing window (early August through mid-September), and certify that they will complete IM residency by the testing date. Program directors submit electronic attestation of residency completion separately. Without that attestation, the candidate cannot test.
The ABIM exam is delivered at Pearson VUE testing centers across the US. Candidates must bring two forms of government-issued ID — typically a driver's license plus a passport or second photo ID. No electronics are allowed in the testing room: no phones, no smart watches, no calculators (basic on-screen calculator is provided). Personal items go in a locker.
Pearson VUE provides scratch paper or a laminated noteboard plus markers; nothing else may be brought in. The full 10-hour testing day includes 4 blocks of 60 questions plus 2 hours of optional break time. Most candidates use the breaks for restroom, hydration, and a quick snack.
ABIM and most program directors recommend 300+ hours of focused study for the certification exam — typically 4-6 months of consistent daily study during PGY-3. The dominant resource is MKSAP (Medical Knowledge Self-Assessment Program), produced by the American College of Physicians and free with ACP membership. MKSAP includes thousands of board-style questions plus a comprehensive textbook organized by content area.
Other widely used resources include UWorld for IM Boards, Mayo Clinic Internal Medicine Board Review, Awesome Review, and the MedStudy Internal Medicine Core Curriculum. Most successful test-takers combine one comprehensive review (MKSAP or MedStudy) with one high-volume question bank (UWorld) over 4-6 months.
The ABIM Foundation is a separate but related nonprofit, also founded and operated by ABIM leadership. While ABIM focuses on certification and MOC, the ABIM Foundation focuses on medical professionalism, transparency, and stewardship of resources. The Foundation's most visible work is the Choosing Wisely campaign, launched in 2012, which partners with more than 80 specialty societies to publish recommendations against low-value medical tests, treatments, and procedures.
Choosing Wisely lists are widely used by medical educators, quality committees, and insurance utilization reviewers. Examples include recommendations against routine annual EKGs in low-risk asymptomatic adults, against imaging for uncomplicated low back pain in the first 6 weeks, against antibiotic use for viral upper respiratory infections, and against routine pre-operative testing in low-risk patients. The Foundation does not enforce these recommendations, but their publication has measurably reduced low-value care utilization in many health systems.
ABIM and MOC specifically have been the subject of significant controversy over the past decade. Physician critics — represented by organizations like the National Board of Physicians and Surgeons (NBPAS), Practicing Physicians of America, and individual high-profile physician bloggers — argue that MOC requirements are expensive, time-consuming, and not supported by strong evidence of patient benefit. Lawsuits filed in 2018 and 2019 alleged antitrust violations and tying of MOC to certification; most were dismissed, but they pressured ABIM to reform MOC.
In response, ABIM has substantially restructured MOC since 2016. The most notable change is the LKA replacement for the high-stakes 10-year exam, introduced specifically because mid-career physicians complained about the cost and disruption of a single 10-hour secure exam every decade. ABIM has also reduced certain MOC fees, broadened the catalog of MOC-eligible CME activities, and improved transparency around governance and finances. Critics argue the reforms are incremental rather than fundamental. Supporters argue MOC drives continuous learning and patient safety. The debate continues, and Diplomates should expect MOC frameworks to keep evolving over the coming decade.
The National Board of Physicians and Surgeons (NBPAS) offers an alternative certification pathway that some hospitals accept for credentialing. NBPAS does not run its own initial certification exam — it certifies physicians who hold or previously held ABMS board certification and meet ongoing CME requirements without an exam. Adoption has been limited; most hospital systems and insurance panels still require active ABIM (or other ABMS) certification.
ABIM has rolled out several notable updates in the 2024-2026 timeframe. The LKA has continued to expand — initially available only for Internal Medicine, it is now offered across most subspecialties, with Cardiology, Endocrinology, Gastroenterology, Hematology, Infectious Disease, Medical Oncology, Nephrology, Pulmonary Disease, and Rheumatology all offering LKA pathways alongside the traditional 10-year exam. Hospice and Palliative Medicine, Geriatric Medicine, and Critical Care Medicine added LKA options in 2024-2025.
ABIM has also clarified its position on the duty hours debate, ITE timing, and MOC documentation. The Knowledge Check-In product — a separate 2-year mini-assessment introduced in 2018 — has been folded into the broader LKA framework, simplifying the menu of options for Diplomates. Annual attestation has been streamlined to a single portal flow rather than separate forms, and fee transparency has improved with itemized billing showing what each fee covers.
The Focused Practice in Hospital Medicine (FPHM) designation continues to grow. Introduced in 2010, FPHM is for board-certified internists practicing primarily in inpatient hospital settings (typically 100+ hospital encounters per year). FPHM is not a separate certification but an MOC pathway with hospital-medicine-specific questions and quality measures. The designation is most useful for hospitalists seeking to demonstrate specialized inpatient competence to credentialing committees, insurance panels, and patients.
Once ABIM-certified, a physician may use the title Diplomate of the American Board of Internal Medicine and the abbreviation FACP (Fellow of the American College of Physicians) if they also hold ACP fellowship, which is a separate professional society credential. The phrase Diplomate, ABIM appears on letterheads, business cards, hospital signage, and physician finders. Some patients confuse Diplomate status with academic degrees — a Diplomate certificate is a professional credential, not an academic doctorate.
ABIM certification opens the door to virtually every career pathway in adult medicine. From a single Diplomate credential, an internist can practice as a hospitalist, outpatient general internist, subspecialist (after fellowship and additional ABIM certification), academic faculty member, medical director, insurance medical officer, or industry physician. Compensation varies dramatically — see our internal medicine salary guide for full compensation ranges by setting and subspecialty, and our internal medicine physician career deep-dive for day-in-the-life detail.
For physicians choosing between Internal Medicine and Family Medicine, the ABIM versus ABFM distinction is meaningful — IM exclusively covers adult medicine and opens subspecialty fellowships, while FM covers pediatrics, OB, and adults with more outpatient focus. See our internal medicine vs family medicine differences comparison for the full breakdown. For visual learners and on-the-go residents, our internal medicine practice test pdf resource offers downloadable question sets formatted for offline study.