Failed the CST Exam? NBSTSA's Retake Rules, the $300 Fee, and a Plan for Attempt Two

Failing the CST is not rare, and NBSTSA's own numbers show it: in 2025, 68.6% of first-time candidates passed, so close to a third did not (Passy arithmetic from NBSTSA's certification data). The rules for trying again are short, and there's no forced wait. What matters more is using the gap well, because the same preparation tends to produce the same result.

CST retake rules at a glance

Sources: the 2026 candidate handbook (re-testing and appeal policy), NBSTSA's policies, FAQ, application page and the 2026 exam application.

Two notes on money. NBSTSA lists no separate AST member rate for retakes; the $230 member rate is for first-time test takers. And NBSTSA's educator FAQs announce a $220 student rate from January 2027 without mentioning retakes, so plan on $300 for a retake unless NBSTSA's launch instructions say otherwise.

Timing a CST retake around the calendar-year limit

The limit counts tests per calendar year, January to December, not per 12 months from your first try. A worked example, with a fictional candidate and Passy arithmetic:

1. First attempt, March 6, 2027. Jordan misses 98 by a few questions.
2. New application, March 9. Standard processing of 2 to 4 weeks puts the new ATT at about March 23 to April 6, with six months to test from then.
3. Second attempt, May 15. About ten weeks after the first, enough time for a real change in preparation. If it doesn't go well:
4. Third attempt, before December 31. This is Jordan's last test of 2027.
5. A fourth attempt couldn't happen until January 2028, when a new calendar year starts the count again.

The flip side helps late-year candidates: someone who tests in November and December 2026 still has three tests available in 2027. The pages checked for this guide state only the calendar-year limit; they don't mention a lifetime cap.

How long to wait is your decision, not NBSTSA's. Retesting within a week or two rarely leaves time to change anything except nerves. Four to eight weeks is a practical range for most candidates (Passy advice). To budget prep for that gap, see whether the planned 30-day or 90-day CST access fits the time before your retake; checkout is not open yet.

What your CST score report can and can't tell you

NBSTSA's handbook says score reports go to every candidate, and its On Test Day page adds that you must return your scratch paper to receive one. The pages and handbook checked for this guide don't describe a breakdown by subject area, so don't plan your restudy around one you may not get.

If your report shows results by area, rank those areas by their scored items: a weak result in Intraoperative Procedures (68 items) costs far more than one in Microbiology (6). If it doesn't, rebuild the picture yourself:

• Complete NBSTSA's free Study Evaluation again, right after the exam while you remember which questions felt hard.
• Write down the kinds of questions that stalled you: a procedure step, an instrument, a dose, a sterilization rule.
• Note whether time was a problem. Breaks don't stop the clock, and you can't return to answered questions after a break.

The CST passing score guide explains how the 98 of 150 works and why it isn't a percentage.

Can you challenge a failed CST result?

Not through an appeal. The handbook says pass or fail scores can't be appealed to NBSTSA's Board of Directors and fall under the complaint policy instead. That complaint must reach NBSTSA within 30 days of the adverse result.

NBSTSA's policies page says a complaint must relate directly to its certification policies and procedures, such as the testing administration center, an expired ATT or a re-test authorization period, and that no other complaints will be considered. It must be in writing, signed and sent to NBSTSA's Director of Operations. NBSTSA says it investigates within 30 days of receiving it, replies in writing, and the outcome is final.

If you missed your appointment rather than failed it, a different policy applies. NBSTSA considers six reasons, including serious illness, a death in the immediate family and jury duty, if you contact it within five business days and send documentation within 30 business days. You may still owe processing fees.

Retaking after on-campus testing (WBT)

On-campus web-based testing is for currently enrolled students testing as a complete graduating group, within 30 days before or after graduation, according to NBSTSA's 2026 on-campus guide. Partial groups have to use PSI test centers after graduation. NBSTSA's pages don't describe an on-campus retake, so plan on retaking at a PSI center and confirm with NBSTSA when you reapply.

A separate case looks like a fail but isn't one. If your proof of graduation doesn't reach NBSTSA within 60 days of an on-campus exam, the educator guidelines say your result is invalidated and you must reapply, pay again and retest. If your graduation is delayed, the on-campus guide says to delay testing until proof can be provided.

A CST re-study plan that changes something

The goal is not more hours of the same review. A plan for four to eight weeks, as Passy's suggestion:

1. Week 1: diagnose. Combine your Study Evaluation ratings, your notes from the exam and any practice results. Pick the two or three sub-areas with the most scored items among those you rated 3, 4 or 5. With 68 items, Intraoperative Procedures belongs on that list whenever you rated it 3 or worse.
2. Change the method, not just the material. Perioperative Care is mostly application questions, so if you studied it from lists, switch to scenarios that ask what you do next in a case. Basic Science is mostly recall, so if it sank you, use short daily flashcard sessions and redo dose calculations until they're automatic. Keep your misses in view: the planned Fix It list keeps every missed CST question for another attempt.
3. Take one official practice form midway. PSI's $40 Self-Assessment Forms A and B are each graded once. If you used one before your first attempt, use the other now. The CST practice test guide compares them.
4. Rehearse the clock. 175 questions in 4 hours is about 82 seconds each. Practice finishing your reviews before any break, since you can't go back afterward.
5. Re-rate before you rebook. If your ratings haven't moved in your heaviest weak areas, a later date is worth more than an early one.

The free CST retake planner turns the areas you found hardest into a week-by-week plan, weighted by NBSTSA's three subject areas.

Your next step after a failed CST

Today, while it's fresh, fill in the Study Evaluation and write down what felt hardest. This week, decide on a target date at least a few weeks out and submit the new application, allowing 2 to 4 weeks for the ATT. Then start the plan above with the 20 free CST practice questions as a quick check, and when you are close to the date, the planned Redemption challenge brings back the CST questions you missed.