AIM Passing Score 2026: Exactly What You Need to Pass

The Exact Passing Score You Need

If you're preparing for the Radio Frequency Interference and Mitigation (RFIM) exam, the number you need to know is simple: 75%. ETA International sets the passing score for RFIM at 75 correct answers out of the 100 questions on the written exam. There's no sliding scale, no scaled scoring formula, and no separate cut score by domain - just a flat 75% threshold applied to the full test.

That flat structure is actually good news for planning purposes. You don't need to guess how ETA weights difficulty across items or worry about a hidden scaled score. Every question is worth the same one point, and you need 75 of them right to walk away certified. For a broader look at how this compares to related certification programs and how difficult the exam feels in practice, see our complete difficulty guide for the AIM exam.

How the RFIM Exam Is Structured

The RFIM certification exam administered by ETA International is a purely written assessment - there is no hands-on or practical demonstration component required. Candidates sit for:

• 100 questions covering all eight competency domains
• A two-hour time limit to complete the test
• A required 75% passing score (75 correct answers)

Testing is arranged through an ETA Certification Administrator and can be delivered via Trapeza online testing, paper-based delivery, or remote proctoring through ExamRoom.AI. If you choose remote proctoring, budget an extra USD 16 on top of the USD 105 exam fee. A scientific or nonprogrammable calculator and scratch paper are both permitted during the exam, which matters given the intermodulation and signal-level math you'll encounter in several domains.

Because the format is entirely multiple-choice/written and time-boxed, pacing matters as much as raw knowledge. With two hours for 100 questions, you have roughly 72 seconds per question on average - enough time to think through calculation-based items if you don't get stuck early. For a full breakdown of registration logistics, testing windows, and how to schedule your seat, check our guide to AIM exam dates and testing windows.

Why Domain Weighting Matters More Than the Raw Percentage

A 75% passing score sounds straightforward until you realize it's an aggregate across eight distinct domains, each drawn from the official 2024 RFIM competency headings (note that ETA's own materials use the source spelling "Principals" for Domain 2):

Because ETA International doesn't publish a minimum score per domain, a candidate could theoretically miss most questions in one domain and still clear 75% overall by performing strongly elsewhere. But in practice, that's a risky strategy - the domains build on each other. Intermodulation questions (Domain 4) often assume you already understand interference types (Domain 3), and interpreting test results (Domain 8) leans on skills from finding interference (Domain 7) and test equipment (Domain 6).

For a topic-by-topic breakdown of what each domain actually tests, including sample concepts and terminology you're expected to know, see our complete guide to all eight AIM exam domains.

Registration, Fees, and What They Have to Do With Your Score

The passing score itself doesn't change based on how you register or test, but the logistics around registration directly affect how prepared you'll be on test day. The base exam fee is USD 105. If you opt for remote proctoring through ExamRoom.AI instead of testing at a physical site, add USD 16 to that total. Testing is coordinated through an ETA Certification Administrator, and you can sit for the exam via Trapeza online testing, paper delivery, or remote proctoring.

A training class is not mandatory to sit for RFIM, but ETA International strongly recommends candidates have hands-on RF-interference and spectrum-analyzer experience before attempting the exam. This isn't a certification you can pass on theory alone - the domains covering test equipment, finding interference, and interpreting test results assume you've actually operated the gear you'll be asked about. For a full cost comparison including upgrade fees and maintenance costs, see our complete AIM certification cost breakdown.

What Happens If You Miss 75%

If you sit for the exam and don't reach 75 correct answers, you're not locked out permanently. ETA International provides one free retake within one year of your initial examination attempt. That's a meaningful safety net - but note that if you choose remote proctoring for the retake, the proctoring charge (USD 16) still applies even though the base exam fee is waived for that one free attempt.

This retake policy should inform how you approach your first attempt. Rather than cramming to barely clear 75%, aim to build a comfortable margin above the threshold, since test-day nerves, unfamiliar question phrasing, or a tricky Intermodulation section can easily cost you a few points you didn't expect to lose. For a data-informed look at how candidates typically perform, see our analysis of AIM pass rate trends.

Scheduling Your Prep Around the Passing Threshold

Since all eight domains feed into the same 75% cutoff, the most efficient prep strategy is to allocate more study time to domains you find conceptually harder rather than splitting your hours evenly. A simple way to structure this in the weeks before your test date:

For a more detailed week-by-week study system, including how to structure practice tests around the actual 100-question format, see our full AIM study guide for passing on your first attempt. You can also run realistic timed practice sessions on our practice test platform to get a feel for the two-hour pacing before test day.

Standalone vs. Journeyman and the Score That Follows You

RFIM certification comes in two tracks: standalone and Journeyman. The 75% passing score applies the same way regardless of which pathway you're pursuing initially - there's no easier version of the written exam for one track versus the other. Where the paths diverge is afterward.

If you earn the standalone RFIM certification and later want to upgrade to Journeyman status, you'll need either a CETa or GCT1 credential, at least two years of documented training or experience, plus a USD 55 upgrade fee. The passing score you achieved on your original RFIM exam doesn't need to be retaken for this upgrade - it's the prerequisite credentials and experience that matter at that stage, not a second exam attempt. For the full eligibility breakdown on both pathways, see our guide to AIM requirements and eligibility.

It's worth understanding this maintenance structure before you even sit for the initial exam, since it shapes the long-term value of clearing that 75% bar. If you're weighing whether the ongoing commitment is worthwhile for your career trajectory, our AIM salary guide and earnings analysis and our broader look at AIM-related job opportunities can help frame the decision. For quick reference on core facts like the passing score, fees, and domain list all in one place, bookmark our one-page AIM cheat sheet.

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