STS Study Guide 2026: How to Pass on Your First Attempt

What You Are Actually Studying For

The Basic Smart Technology Systems (STS) certification is issued by ETA International and is aimed at practicing technicians who install, connect, and support smart home and light commercial systems. Before you open a single study resource, get clear on what the credential measures. It is a written knowledge examination built from a published list of competencies, not a hands-on skills test, and not a general electronics theory exam.

That distinction shapes everything about preparation. ETA states that exam questions derive from its Basic STS competency document, which means the most reliable syllabus is the one the issuer itself publishes. If you want background on the credential before diving into prep, our overview of what STS certification is and the explainer on what STS stands for cover the basics. This guide assumes you have decided to sit the exam and want the most direct route to passing it.

Exam Mechanics: Format, Fee, and Testing Rules

Knowing the container your knowledge must fit into removes a surprising amount of test anxiety. Here is what ETA publishes for the Basic STS exam.

A few details deserve emphasis. First, the question count is published as a range of 75-80, and ETA does not publicly split that into scored and unscored items, so do not plan around a specific number of questions you can miss. Second, the item type is not specified in the public sources, so avoid assuming the exam is entirely multiple choice; prepare to read carefully and answer whatever format appears. Third, ETA offers the core STS exam at half price when it is taken at the same time as at least one endorsement, which matters if you already know you want to add an endorsement.

For a line-by-line look at money, see our STS certification cost breakdown. For the scoring threshold specifically, the STS passing score guide explains what 75% means in practice.

The 12 Competency Areas, Grouped by How You Will Study Them

ETA's competency document contains 12 numbered top-level headings. No percentage weights are published, so no domain can honestly be called the "highest weight." The practical response is breadth: every area is fair game, and a weak spot in any one of them can cost you. For a heading-by-heading walkthrough, see the complete guide to all 12 STS content areas. Here, the areas are grouped by the kind of study they demand.

Start With the Field Skills You Can Verify

Because the exam draws from a competency list that reads like a technician's job description, your own work history is a diagnostic tool. Before you buy anything, spend an hour walking through the 12 headings and marking each as "I do this weekly," "I have done this," or "I have only read about this." That honest sorting tells you where to invest.

If you come from low voltage or security installation

You likely have a head start on Domains 3, 4, 5, and 10. Your risk is the softer areas: Industry Standards vocabulary, Customer Orientation and Documentation, and Premises Restoration. Experienced installers often know how to do these things but have never had to name the principle behind them, and exam questions reward the named principle.

If you come from AV or networking

Communications Systems and wireless topics may feel comfortable. The gap tends to be Safety, Electrical Basics, and the physical cabling domains, where you may have relied on others in the field. Lean on hands-on exposure where you can, and treat connectorization as a topic with correct and incorrect practices.

If you are new to the trade

Plan for a longer runway and read the full competency document slowly. The related certifications ETA highly recommends (CAT, DCI, DVE, FOI, FOT, FOT-OSP, or TTT) exist because they build the cabling and systems foundation this exam assumes. They are recommendations, not requirements, but they signal where the knowledge base comes from. Our STS requirements guide details exactly what is and is not mandatory.

A Domain-Driven Study Sequence

Since weights are not published, sequence your study by dependency rather than by exam percentage. Foundations first, because later topics lean on them; judgment-heavy areas last, because they integrate everything else. This single scheduling approach is the only generic structure worth following here, and it is tied directly to the domains.

A four-week plan suits someone already working in the field. If you are newer to the trade, stretch each block, and keep the same order. Use our STS difficulty guide to calibrate how much time your background suggests you need.

Why this order works

Troubleshooting questions are rarely about one isolated fact. A single scenario might touch safety, cabling, documentation, and customer communication at once. By placing Domain 12 last, you reach it carrying the vocabulary and mental models from every earlier domain, which is exactly what scenario-style reasoning requires.

Practice Materials and What They Can and Cannot Do

Be realistic about the resources available. ETA advertises a USD 59.95 study resource in the STS section of its site, but the linked public eITPrep catalog visibly identifies the Security and Surveillance endorsement course, not a separate Basic STS course. Availability of a dedicated core-STS course could not be confirmed, so check directly with ETA before purchasing anything on the assumption that it covers the Basic exam.

ETA's membership page lists STS member practice-exam access. Membership is optional and is not required to sit the exam, and practice access does not give you actual certification questions. Treat any practice exam as a way to find weak domains and rehearse timing, not as a preview of the real test.

Because no verified pass rate exists in the public sources, avoid benchmarking yourself against rumored numbers. The STS pass rate article explains what is and is not known. Your best benchmark is simple and measurable: consistently scoring above 75% on timed, domain-balanced practice, with a margin for nerves.

Test-Day Logistics That Trip People Up

Many preventable problems happen before the first question appears. ETA's rules are specific, so read them rather than assuming.

• Proctor and photo ID: A proctor is required, and you need valid photo identification.
• Calculator and scratch paper: ETA permits scratch paper and a nonprogrammable or scientific calculator. Used scratch paper must be surrendered at the end.
• Phones and devices: Personal electronic devices such as phones are prohibited.
• Leaving the room: ETA's general rules prohibit leaving once testing starts, so handle everything beforehand.
• Remote testing: You need a webcam, microphone, a suitable computer, and reliable connectivity, with registration arranged through ETA. Remote proctoring carries an added USD 16 charge for the two-hour session, and those charges remain payable even on a free retake.
• Open or closed book: Specific STS open-book and adaptive-testing rules were not verified, so confirm the policy with ETA when you register rather than assuming.

For scheduling windows and registration timing, see the STS exam dates guide.

Pacing the two hours

With 75-80 questions in 120 minutes, you have roughly a minute and a half per question on average. Work through the whole exam once, answering what you know, and flag anything that requires extended reasoning. Calculation questions from Electrical Basics are worth doing carefully on scratch paper rather than rushing, since a slip in arithmetic is an avoidable loss.

After You Pass: Maintenance and Next Steps

The certification runs on a four-year term with required maintenance. For general non-hands-on maintenance, ETA requires a maintenance form and USD 25 per year (USD 100 over the four years), plus either 10 continuing-education contact hours per year (40 over the cycle) or an Employer Verification Form completed by a supervisor. Annual submission is recommended, which spreads the effort and avoids a last-minute scramble.

If you are weighing whether the investment makes sense for your career, the STS ROI analysis, the STS salary guide, and the STS jobs overview look at the employment side. For deeper background on the training landscape, see our STS training page.

Frequently Asked Questions

Preparing well comes down to reading the official competency document, honestly assessing your field experience against all 12 areas, and verifying your readiness with timed practice. For a compact refresher in the final days, the STS cheat sheet distills the must-know facts.