Most people preparing for a contractor license exam assume “open book” means they can carry in whatever they own. That assumption costs candidates their exam fee every week. Proctors turn away reference books at the door for reasons that have nothing to do with the content inside them, and a book that is perfectly legal in one state gets confiscated in the next.
If you are still working out the shape of your exam, start with our guide to how many questions are on the contractor licensing exam. This guide covers what open-book actually means in practice, the rules that apply almost everywhere, and the specific reference lists for several states. Every figure below comes from the state’s own candidate information bulletin or licensing division, not from a prep vendor.
Open book does not mean open bag
Across the major testing vendors (PSI, Prov, Pearson VUE, ICC), the same handful of rules show up again and again. Learn these once and they travel with you.
- References must be bound. A three-ring binder of printouts is usually fine when the state explicitly allows a printed manual, but loose pages, stapled packets, and photocopied chapters are not.
- You may mark the book before the exam, never during. Highlighting, underlining, and indexing done in advance are almost always permitted. Writing anything during the session gets the reference confiscated, and in several states the incident is reported to the licensing board.
- Permanent tabs only. Post-it notes and any other removable tab are prohibited in most bulletins, because a removable tab can carry writing in and out of the room.
- Nothing extra between the pages. Loose paper tucked into a code book will be removed and confiscated, even if it is blank.
- Editions are pinned. For code questions the exam is scored against one specific edition. A newer edition of the code is not a safe substitute, even though newer editions of non-code references usually are.
That last point catches more people than any other. If the bulletin says the 2018 International Mechanical Code, the 2021 edition will not help you and may actively hurt you, because section numbering shifts between cycles.
The reference list is exam-specific, not state-specific
Here is the trap that surprises even experienced tradespeople: two exams from the same state board, taken in the same building, can have completely different reference lists.
Idaho is the clearest example. The Idaho Division of Occupational and Professional Licenses administers its HVAC exams in house. Per the DOPL HVAC exam bulletin, the Journeyman and Specialty Journeyman exams allow the 2018 International Mechanical Code and the 2018 International Fuel Gas Code, and the bulletin states plainly that commentaries are not permitted.
The HVAC Contractor exam, from the same division, allows exactly one reference: the DOPL Contractor’s Business and Law Reference Manual. No code books at all. That is because the Contractor exam is not a trade exam. All 100 of its questions come from that business and law manual, covering licensing, contracts, lien law, payroll taxes, insurance, estimating, and OSHA safety. A candidate who spends three months studying the mechanical code for that exam has studied the wrong subject entirely.
The lesson generalizes: read the reference list for your specific exam, not for your trade or your state.
What several states actually allow
New Mexico EE-98 Electrical Contractor
Administered by PSI for the New Mexico Regulation and Licensing Department, Construction Industries Division. The EE-98 is a three-part exam. Part 1 (Commercial and Industrial) is 80 questions in 200 minutes, Part 2 (Residential) is 40 questions in 100 minutes, and Part 3 (Specialties) is 50 questions in 135 minutes. All are open book and all require 75 percent to pass.
Permitted: NFPA 70 National Electrical Code (2020) or the NEC Handbook, the New Mexico Electrical Code (NMAC 14.10.4, 2020), and the National Electrical Safety Code (2007).
Explicitly not permitted: the American Electricians’ Handbook, Ugly’s Electrical References, and the Lineman’s and Cableman’s Handbook. Those three are allowed in other states, which is exactly why candidates bring them by habit and lose them at the door.
If Texas is your target state instead, our Texas electrical contractor license guide covers TDLR requirements end to end.
Delaware Master Electrician
Administered by Prov for the Delaware Division of Professional Regulation. Open book, 80 questions, three hours, 75 percent to pass, based on the NEC as adopted by Delaware.
Permitted: the American Electricians’ Handbook and the NEC. Note that this is the same handbook New Mexico bans. Tabs and highlighting are allowed, but no Post-it notes, no photocopies, and no test-prep guides in the room.
Montana Journeyman and Master Plumber
Administered by IAPMO for the Montana Board of Plumbers. Open book, three hours, 70 percent to pass. The written Journeyman exam is 100 questions and the Master exam is 125.
You bring your own tabbed copy of the 2021 Uniform Plumbing Code. The statutes and rules packet is handed to you at the exam, so there is no need to source it in advance. Both licenses also require a separate practical exam that no multiple-choice practice can prepare you for.
California plumbers should note the contrast: the CSLB exams are closed book. See our C-36 plumbing contractor license guide for how that changes preparation.
South Dakota electrical
ICC administers these for the South Dakota Electrical Commission. The Journeyman exam (531) is 80 questions and the Electrical Contractor exam (530) is 100. Both are referenced solely to NFPA 70 (2023), and Ugly’s Electrical References is permitted in any edition. South Dakota issues an Electrical Contractor license rather than one titled Master Electrician, which matters when you are searching for study material.
Florida construction trades
The Florida Department of Business and Professional Regulation runs its construction exams as computer-based tests through Pearson VUE, in a reference-lookup format with generous time. The General Contractor trade parts are 60 questions each with four and a half hours allowed, which works out to more than four minutes per question. Business and Finance is 120 questions in six and a half hours.
Those time allowances tell you something about how the exam is designed. It is testing whether you can find and apply the right provision, not whether you memorized it.
Closed-book exams still exist
Do not assume every contractor exam is open book. The Nevada Contractors’ Management Survey, required of the qualified individual on every Nevada license, is 60 scored questions in 120 minutes with a 75 percent pass mark, and it is not an open-book exam. North Dakota’s plumbing exam is split: Part 1 is 100 closed-book multiple-choice questions, while Parts 2 through 4 are open-book completion exercises.
California is closed book throughout, and our CSLB exam day guide covers what you can and cannot carry in there. Mixed formats like North Dakota’s are worth planning for specifically, because the study approach for a closed-book section is completely different from the lookup skills that carry an open-book section.
How to actually use an open book
Being allowed a code book and being able to use one under time pressure are different skills. A few things that separate candidates who finish comfortably from those who run out of time:
- Tab by task, not by chapter. Chapter tabs tell you where you already knew to look. Tabs for the ten calculations you will certainly be asked to perform save real minutes.
- Practice the lookup, not just the answer. When you work practice questions, physically find the provision in the book. The exam measures retrieval speed as much as knowledge.
- Know which tables you will need cold. Ampacity, fixture units, duct sizing, load calculations. Knowing the table exists and where it lives is worth more than memorizing its contents.
- Do the marking early. Highlighting has to be finished before you walk in, and doing it as you study is what makes it useful rather than decorative.
Before you register
Bulletins change between editions, and the reference list is the part most likely to move when a state adopts a new code cycle. Three things worth confirming on the current bulletin for your specific exam:
- The exact edition year of every code book named.
- Whether handbooks and commentaries are treated as permitted references or as prohibited study aids.
- Whether your exam has a separate business and law component with its own, entirely different reference list.
Get those three right and you have removed the most common avoidable reason candidates lose an exam attempt before answering a single question.
From there it is a question of method rather than material. Our guide on how to study for a contractor license exam covers the practice routine that builds lookup speed, and you can choose your state to find practice exams built to your exam’s real length, time limit, and passing score.