Why a prospect sent you this Excel file
If you sell a B2B SaaS product and a mid-market or enterprise prospect just moved from "we'd like to buy this" to a legal or procurement review, a vendor security questionnaire is a normal, expected part of that process — not a sign the deal is in trouble.
Buyers send these because they're taking on risk the moment your product touches their data, their employees' credentials, or their own customers' information. Their security or procurement team has a mandate — often driven by their own customer contracts, cyber insurance policy, or board-level risk program — to document that every vendor they bring on has been reviewed before a contract is signed.
For a first-time founder, the questionnaire can look intimidating: a spreadsheet with 100–300 rows, spanning topics from encryption algorithms to background-check policy to disaster recovery testing. Most of it is boilerplate the buyer reuses across every vendor they review, regardless of size. It is not a test written specifically to catch you out — it is the buyer's standard intake form, and plenty of the questions may not fully apply to a small company yet. The reasonable move is to answer accurately, including where you're still building something out, rather than treat the form as pass/fail.
What a vendor security questionnaire is trying to assess
Underneath the specific wording, almost every questionnaire is probing the same handful of risk categories. Knowing them in advance makes a 200-question form much less overwhelming, because you can map most rows back to one of these buckets:
- Data handling and encryption — what customer data you collect, where it's stored, whether it's encrypted at rest and in transit, and how long you retain it.
- Access control and identity — who inside your company can reach customer data, whether you enforce least-privilege access, and whether you support SSO/MFA for your own customers.
- Infrastructure and cloud security — which cloud provider(s) you run on, network segmentation, logging, and how you patch and monitor your systems.
- Application security — whether you run code review, vulnerability scanning, or penetration testing, and how quickly you remediate what you find.
- Incident response — whether you have a documented plan, and what your breach-notification timeline to customers looks like.
- Business continuity and disaster recovery — backup frequency, recovery time objectives, and whether you've actually tested a restore.
- Subprocessor and vendor management — every third-party service that touches the buyer's data through you (hosting, email, analytics, support tooling), because the buyer is inheriting your supply chain risk too.
- Compliance status — SOC 2, ISO 27001, HIPAA, PCI, or industry-specific frameworks, and whether you hold, are pursuing, or don't yet have any of them.
- People and process — employee background checks, security-awareness training, and offboarding procedures.
The buyer's underlying question, in every one of those categories, is the same: if something goes wrong on your side, how much exposure does that create for us, and how would we find out? Answering with that framing in mind makes the individual questions easier to interpret.
Common formats: CAIQ, SIG-Lite, and custom procurement spreadsheets
Most questionnaires you'll receive fall into one of three shapes. Recognizing which one you've been sent tells you roughly how long it will take and whether a template already exists for it.
CAIQ
The Cloud Security Alliance's Consensus Assessments Initiative Questionnaire. A standardized, publicly published set of yes/no-plus-narrative questions mapped to the Cloud Controls Matrix. Common with buyers that specifically care about cloud-service risk. Because it's standardized, a completed CAIQ can often be reused with only minor edits across multiple prospects.
SIG / SIG-Lite
The Shared Assessments Standardized Information Gathering questionnaire. The full SIG runs to well over a thousand rows across every risk domain; SIG-Lite is a condensed subset commonly sent to smaller or lower-risk vendors. Format and phrasing are standardized, so once you've answered it once, most future SIG-Lite requests are largely a copy-and-adapt job.
Custom procurement Excel
A spreadsheet the buyer's own security or procurement team built in-house, sometimes years ago. Content usually overlaps heavily with CAIQ/SIG-Lite topics, but structure, tab layout, and exact wording vary company to company — there's no shared template to reuse, so each one takes a fresh read-through even if the substance repeats.
Whichever format arrives, the same underlying answers about your data handling, access control, and incident response tend to satisfy 80–90% of the rows — the remaining work is almost always mapping your existing answers to that specific buyer's wording and filling in anything genuinely new.
Who typically needs to be involved in answering it
At a larger company, a questionnaire routes through a dedicated security or GRC team. At an early-stage B2B SaaS company, the same information usually lives in the heads of two or three people, and part of answering a questionnaire well is simply pulling it together in one place for the first time.
Founder / engineering lead
Owns the questions about architecture, encryption, access control, logging, and how your infrastructure is actually configured. Usually the only person who can answer these accurately without guessing.
Whoever owns security policy
Confirms whether documented policies (incident response plan, data retention policy, offboarding procedure) exist, or whether they need to be written before you can answer honestly.
HR / people ops
Answers questions on background checks, onboarding/offboarding, and security-awareness training — often a short, separate section of the form.
Legal / operations
Reviews any answer that references contractual commitments — breach notification timelines, subprocessor lists, data processing terms — before it's submitted, since these can become binding representations.
It's normal for one founder to be three of those four people at the same time. The goal isn't to have a separate specialist for each row — it's to make sure someone with real knowledge of the answer is the one supplying it, rather than a best guess.
A first-timer's checklist before you start answering
Before opening row one, a short setup pass saves rework and produces answers that hold up under a reviewer's follow-up questions:
- Gather what already exists. Security policy, subprocessor/vendor list, architecture diagram, any past penetration test or vulnerability scan report, prior questionnaire responses (even for a different prospect) — collect these first so you're transcribing from real documents, not memory.
- Note the deadline and delivery format. Confirm whether the buyer needs the same file back, a portal submission, or a signed cover letter — formatting mistakes are a common reason a completed questionnaire bounces back.
- Identify genuine gaps up front. Some rows will describe a control you don't have yet (a certification, a formal pentest, a written DR test). Decide now how you'll phrase that honestly — a clear "not yet, planned for [timeframe]" is a normal and defensible answer; a fabricated "yes" is not.
- Assign one owner and one reviewer. One person drafts, one person (ideally with legal or leadership visibility) reviews before it goes out — especially for any answer that touches contractual commitments.
- Sort questions by who can answer them using the roles above, so technical rows go to the person who actually configured the systems rather than whoever opened the spreadsheet first.
- Save your answers in a reusable format. This questionnaire will not be the last one. Keeping approved answers, organized by topic, turns every future request into an edit-and-resubmit rather than a start-from-scratch exercise.