Ohio Plumbing License Exam — What to Expect on Test Day

Two Exams, One Session

The OCILB commercial plumbing contractor license requires passing two separate exams, both administered by PSI Services:

Trade Exam: 100 questions, 4-hour time limit. Covers the Ohio Plumbing Code, installation standards, fixture requirements, drainage design, and materials specifications.

Business and Law Exam: 50 questions, 2-hour time limit. Covers ORC Chapter 4740, the Ohio Administrative Code (OAC 4101:16), business formation, contract law, insurance requirements, and employer obligations.

Both exams require a minimum passing score of 70%. You receive your score immediately upon completion — no weeks-long waiting period for results.

Scheduling and Fees

Schedule both exams through PSI Services' online portal. If you book both for a single session, the combined fee is $100. Taking them separately costs $69 each.

You cannot schedule your exams until the OCILB has approved your application. The board reviews applications on a bimonthly cycle, so factor that waiting period into your timeline. Once approved, you typically have one to two weeks of lead time to book your PSI appointment.

Your board approval expires one year from the approval date. If you do not pass both exams within that window, you must reapply to the OCILB with a new application and fee.

Open-Book Format and Reference Rules

Both exams are open-book. You can bring approved reference materials — the Ohio Plumbing Code, ORC Chapter 4740, and other board-specified references. You are allowed to use permanent tabs and highlighting in your reference books.

What you cannot do: write personal handwritten notes directly on your reference pages. Handwritten annotations on the reference materials themselves are strictly prohibited. Separate personal note sheets are also not allowed — the only written material at your testing station should be the approved references and the materials PSI provides.

Bring clean, well-tabbed copies of your references. Knowing where to find information quickly matters more than memorizing code sections when you have a 4-hour time limit and 100 questions.

Retake Rules

If you fail either exam, you must wait 60 days before retesting. Each retake costs $69 per exam. You are limited to five attempts per year on each exam.

If you pass one exam but fail the other, you only need to retake the failed exam — your passing score on the other one holds. But remember the one-year approval window: if you exhaust your retake attempts or run out of time, you restart the OCILB application process from scratch.

Before the Exam: Get Your Prerequisites Done First

The exam is the middle of the process, not the beginning. Before PSI will let you test, you need:

1. OCILB application approved — notarized application packet, five years of W-2 documentation, $25 application fee, bimonthly board review
2. Background check cleared — BCI and FBI fingerprint results sent directly to the Division of Industrial Compliance ($50–$75, valid for one year)

After the exam, you still need:

3. Proof of insurance — $500,000 general liability policy naming OCILB as certificate holder
4. License fee — $25 to the OCILB
5. Local municipal registrations — separate fees and bonds for each city where you pull permits

The Ohio Plumber License Guide walks through the full timeline from application to test day to license issuance, including how to coordinate your background check validity window with the bimonthly board review cycle so nothing expires before you test.

See more Ohio guides →