CNN Cheat Sheet 2026: One-Page Review of Must-Know Facts

Exam Snapshot: The Numbers That Matter

If you only have five minutes before your test-day nerves kick in, these are the numbers to memorize. The Certified Nephrology Nurse (CNN) exam is developed by the Nephrology Nursing Certification Commission (NNCC) in partnership with the Center for Nursing Education and Testing (CNET), and it's delivered as computer-based testing at PSI test centers nationwide.

The exam itself is 150 multiple-choice questions administered over three hours. Roughly 25 of those items are unscored pilot questions being field-tested for future exams - you won't know which ones they are, so every question deserves your full attention. For a deeper walk-through of how the test is structured and what makes it challenging, see How Hard Is the CNN Exam? Complete Difficulty Guide 2026.

Registration Mechanics and Fees

Before you can sit for the exam, you'll register through NNCC and schedule your test at a PSI location. The standard exam fee is $350, while candidates who qualify as partner members pay a reduced fee of $300. That's a modest difference, but it adds up if your employer isn't reimbursing exam costs - worth checking before you pay full price.

These fees cover the exam itself, not any prep materials, contact hours, or potential retake costs. For a complete accounting of what certification actually costs from application to renewal, review CNN Certification Cost 2026: Complete Pricing Breakdown.

2026 Eligibility Changes You Need to Know

This is the section that trips up experienced nurses who assume the requirements haven't changed. Effective Summer 2026, NNCC updated eligibility for the CNN credential in three important ways:

• License: A current, unrestricted RN license from a U.S. state or territory.
• Practice hours: 2,500 hours of qualifying nephrology nursing practice within the prior two years.
• Contact hours: 30 approved nephrology contact hours completed within the prior two years.

Notably, a BSN is no longer required to sit for the exam. This opens the CNN pathway to more associate-degree RNs who have strong clinical nephrology experience but hadn't completed a bachelor's degree. If you're mapping out your eligibility timeline, CNN Requirements 2026: Eligibility, Prerequisites & How to Qualify walks through each requirement in detail.

Domain-by-Domain Cheat Sheet

The April 2026 blueprint (effective September 1, 2026) organizes the exam into five domains. Here's the weighting at a glance:

Notice that Domains 1 and 2 together account for well over half the exam. If your study time is limited, this table alone should reorder your priorities. For the full content outline within each domain, cross-reference CNN Exam Domains 2026: Complete Guide to All 5 Content Areas.

Must-Know Clinical Topics by Domain

Beyond the domain outlines, certain clinical concepts show up repeatedly across item writers' question banks. Candidates consistently report needing fluency in:

• Interpreting lab trends (BUN, creatinine, potassium, phosphorus) in context of both AKI and CKD
• Distinguishing complications specific to PD versus hemodialysis versus CRRT
• Recognizing medication dosing adjustments tied to renal clearance
• Applying life-span considerations - pediatric fluid management differs meaningfully from geriatric management

The exam's multiple-choice format tends to favor application-based stems over pure recall - expect a short clinical vignette followed by a "what should the nurse do next" style question rather than a definition-matching format. This style rewards candidates who've practiced with realistic scenario questions rather than flashcards alone.

Scoring and Passing Threshold

The CNN exam uses a criterion-referenced passing standard set through an Angoff study. Currently, that standard requires approximately 74% correct to pass. This isn't a fixed raw score - because roughly 25 unscored pilot items are mixed into the 150 questions, your actual passing threshold is based on scored items only, and NNCC does not disclose which items are scored versus pilot.

For a detailed explanation of how the passing standard is calculated and what it means for your target score, see CNN Passing Score 2026: Exactly What You Need to Pass.

Final-Week Review Plan

Generic study techniques like spaced repetition only help if you're applying them to the right content in the right order. Given the domain weighting, your final two weeks should be lopsided toward Domains 1 and 2.

For a complete week-by-week structure that spans the full prep window rather than just the final two weeks, see CNN Study Guide 2026: How to Pass on Your First Attempt. Practicing full-length scenario questions on the main practice test platform is one of the most reliable ways to identify weak domains before test day.

Renewal and Recertification Facts

Certification doesn't end at your pass notification - the CNN credential is valid for three years. To renew, you'll need 1,500 hours of nephrology nursing practice plus 45 contact hours, of which at least 15 must be nephrology-specific. Alternatively, you can recertify by retaking the exam.

Mark your renewal window early. Waiting until the final months of your three-year cycle to accumulate 45 contact hours (with 15 nephrology-specific) is a common and avoidable stress point.

Who Hires CNNs

The CNN credential signals depth across the full continuum of kidney care - acute, chronic, and both dialysis modalities plus transplant. Employers who actively seek CNN-certified nurses include:

• Inpatient nephrology and critical care units managing AKI and CRRT
• Outpatient dialysis centers running both in-center hemodialysis and home programs
• Peritoneal dialysis and home hemodialysis training programs
• Transplant centers requiring post-transplant nursing expertise

If you're weighing whether the credential translates into career or pay advantages, CNN Salary Guide 2026: Complete Earnings Analysis and Is the CNN Certification Worth It? Complete ROI Analysis 2026 both dig into that question directly. You can also browse current openings that specifically list the credential through CNN Jobs.

Frequently Asked Questions