What a state nexus questionnaire is, and what it isn't
The letter landed. Before anything is written, before anyone speculates about what it means for the next 12 months, the first decision is the right classification. Three documents arrive from state revenue departments with meaningfully different legal weights, and each calls for a different response posture.
A nexus questionnaire is a formal information request. The state suspects nexus may exist and is asking the brand to provide the facts that support or refute that suspicion. The process is pre-audit. No formal examination proceeding is open. The brand is not under review. The response deadline is defined by the letter, typically 30 days from the letter date, and failure to respond produces a nexus determination by default. That default determination is what the state uses as the basis for a compliance demand or registration notice.
A registration request follows a positive nexus determination, either from a questionnaire response or from the state's own analysis. The state has concluded that nexus exists and is now asking the brand to complete sales tax registration. Some states issue a registration notice immediately after a questionnaire produces a positive response. A registration request is not a questionnaire; it does not require the same deliberative data-and-counsel review process.
An audit notice is a formal examination proceeding with statutory authority behind it. An audit notice carries subpoena-equivalent information demands, formal statutory timelines, and potential penalties for obstruction or non-compliance. An audit response is a legal proceeding requiring outside counsel from day one, and the document standards are different at every step.
A nexus questionnaire response and an audit response share one characteristic: both create a written record the state will hold. Otherwise they require different levels of counsel involvement, different urgency, and different resource deployment. A controller who treats a questionnaire as an audit deploys resources unnecessarily. One who treats it as routine optional correspondence may miss the deadline and hand the state a default determination that costs far more to contest than a correctly filed response would have.
The financial stakes of this classification are real. The questionnaire response sets the factual record that drives the next 12 to 36 months of remediation work. How the brand characterizes its sales history, channel mix, and physical presence determines what the state has on record for any subsequent assessment. It also shapes M&A diligence: acquirers routinely review historical sales tax compliance, and the questionnaire response file is one of the first documents their tax counsel requests.
What California, New York, Massachusetts, Washington, and Illinois actually ask
Each state's questionnaire asks the same underlying question, what facts establish nexus, but the form and measurement frame differ by state. The five states most likely to send questionnaires to a growing Shopify or Shopify Plus brand in the $20M to $80M range are the ones with the highest remote-seller enforcement activity.
| State | Form | Key question categories | Threshold being measured |
|---|---|---|---|
| California | CDTFA-345-WEB | In-state sales by year (4-year lookback), physical presence indicators, marketplace channels, related-entity sales under IRC §267(b), prior registration history | $500,000 in gross sales, Cal. Rev. & Tax. Code §6203 [1] |
| New York | DTF Nexus Questionnaire | In-state gross receipts by quarter (4-quarter lookback), transaction count by quarter, physical presence, marketplace channels, employees and contractors, corporate structure | $500,000 AND >100 transactions per 4 sales tax quarters, NY Tax Law §1101(b)(8) [2] |
| Massachusetts | DOR Nexus Questionnaire | In-state sales by year, physical presence indicators, marketplace activity, inventory locations, employee and contractor presence | $100,000 in Massachusetts sales, 830 CMR 64H.1.9 [3] |
| Washington | DOR Business Activity Questionnaire | Gross receipts into Washington (cumulative, including facilitated and exempt sales), physical presence, B&O tax activity, marketplace channels | $100,000 in cumulative gross receipts including exempt and facilitated sales, RCW 82.08.052 [4] |
| Illinois | DOR Nexus Questionnaire | In-state sales by 12-month rolling period, physical presence indicators, marketplace channels, prior nexus positions | $100,000 in gross receipts from sales of TPP; 200-transaction test repealed effective 1/1/2026 via P.A. 104-0006 [5] |
Three form-level details catch operators before they reach the substantive questions:
California asks about related-entity sales under IRC §267(b). California aggregates sales across related persons when measuring the $500,000 threshold (Cal. Rev. & Tax. Code §6203)[1]. A brand with an operating LLC, a holdco, and an IP-holding entity needs to read the related-entities section carefully before entering any numbers. Any question about affiliated persons or related parties on CDTFA-345-WEB routes through counsel.
New York asks about dollar volume and transaction count separately, and both figures need to come from the same four-quarter measurement window. Using calendar-year totals where the form asks for sales-tax-quarter data produces a mismatched response. New York uses an AND test, not OR: both $500,000 in gross receipts AND more than 100 transactions must be met over the same four quarters (NY Tax Law §1101(b)(8))[2]. A brand below one of those two figures has not met the economic nexus threshold, but answering with mismatched data creates a different kind of exposure.
Washington's form includes questions about B&O (Business and Occupation) tax, a separate Washington gross receipts tax distinct from sales tax. These are two separate obligations. If B&O questions appear on the Washington BAQ, flag them to counsel before answering; they are not the same analysis as the sales tax nexus questions on the same form.
Once the questionnaire is returned and nexus is confirmed, the registration chain begins. TaxCloud handles registration across confirmed states, with native Shopify and Shopify Plus integration and the filing infrastructure to start collecting and remitting from the confirmed effective date.
The answer-direct vs. counsel-first taxonomy
The practical value of separating these two categories is that it lets the finance team move fast on data assembly while counsel focuses only on questions with legal exposure. Data work can and should happen within the first week of receiving the letter. Counsel's review covers a narrower set of questions and should not slow the data work down.
Answer directly, without routing through counsel before entry
- In-state sales history by period. Pull from Shopify's tax reports or order exports with state-level breakdown, Amazon Seller Central settlement reports by state, and any active marketplace channel data. Match the time window the form specifies, by calendar year or by sales-tax quarter. Report gross sales from platform data as reported, not estimated or rounded.
- Channel mix and marketplace activity. Does the brand sell on Amazon? Walmart Marketplace? TikTok Shop? These are factual questions about current and recent operations. Yes or no, with volume if the form requests it.
- Physical presence, current footprint. Current warehouse addresses, employee headcount and states of residence, 3PL relationships, and office locations. Present-tense facts about what the business is today, not retrospective admissions about prior periods.
- Product categories. Most forms ask about product type for taxability mapping. Answer based on the current catalog.
Route through counsel before entry
- Prior registration history. If the form asks whether the brand has ever been registered in this state, or has any prior collection history there, the answer goes through counsel first. This question can reveal a gap between when nexus existed and when the brand registered, creating an admission of the exact lookback window an auditor wants confirmed.
- "Intent to register" or "plans to collect." Some forms ask when the brand plans to begin collecting. This is a forward-looking admission with legal consequences depending on whether VDA or standard registration is the right path. Counsel determines what goes in this field.
- Historical nexus posture. If the form asks when the brand believes nexus was established, counsel writes the answer. That response sets the starting date for any assessment.
- Related-entity and corporate-structure questions. On California's form especially, questions about related entities under IRC §267(b) can expand both the measurement base and the liability exposure. Counsel handles these.
- "Known non-compliance" questions. If the form asks whether the brand is aware of unfiled returns or uncollected tax, that is counsel-only territory.
The dividing line: factual present-tense data about what the business is and what it sold is answer-direct. Any question that asks about the past in ways that could establish a liability start date or create an admission of prior non-compliance is counsel-first.
Response deadline math by state
The default response window across all five states is 30 days from the date of the letter. The deadline mechanics differ.
| State | Default deadline | Extension policy | Consequence of no response |
|---|---|---|---|
| California | 30 days from letter date | Written request to assigned CDTFA officer before deadline; extensions granted but CDTFA holds firm, typically 14-30 additional days | Default nexus determination; CDTFA may issue a compliance demand or registration notice |
| New York | 30 days from letter date | Formal written request to assigned DTF officer required; DTF is the strictest of the five on granting extensions | Default nexus determination; DTF may proceed to proposed assessment |
| Massachusetts | 30 days from letter date | Generally flexible on a first extension request; written or phone request before deadline | Default nexus determination |
| Washington | 30 days from letter date | Written request to assigned DOR officer; extensions available | Default nexus determination; WA DOR actively pursues non-responders given its broad gross-receipts measurement basis |
| Illinois | 30 days from letter date | More flexible on extensions; during the Remote Retailer Amnesty Program (August 1 to October 31, 2026), additional runway may be available through the amnesty channel | Default nexus determination; non-response during the amnesty window may foreclose amnesty eligibility |
Four calendar-math points that the controller needs to track from the day the letter arrives:
The clock starts on the letter date, not the receipt date
USPS delivery takes three to five business days. A 30-day window from the letter date can be 24 to 26 days from when the envelope arrived. Mark the actual due date, calculated from the letter date, on day one.
Extensions protect the response deadline but do not pause the VDA clock
An approved extension keeps the questionnaire response channel open. It does not change when the state considers itself to have made "contact" for VDA-disqualifier purposes. The VDA sequencing issue covered in the next section is unaffected by any extension granted.
Proof of response delivery is not the same as proof of the state's letter being received
The state wants confirmation the response arrived before the deadline. Send via certified mail with return receipt, or file through the state's portal and save the submission confirmation with timestamp immediately after filing.
Calendar-month math
A letter dated the 28th of one month means the 30-day window closes the 27th of the following month unless the intervening month is shorter. Add 30 days to the letter date, not to the date the envelope arrived.
The VDA sequencing trap: deciding before you respond
Most state VDA programs include a "no prior contact" requirement: the state must not have already initiated contact with the taxpayer about the liability period in question. A nexus questionnaire response that acknowledges in-state taxable activity typically establishes that contact. Once the response goes out, the brand is generally ineligible to enter VDA in the same state for the same liability period.
The sequencing implication: the remediation decision and the questionnaire response are not two sequential steps. They are parallel decisions with a constraint. The remediation decision must be made before the response is finalized and sent.
VDA
The brand, through counsel, proactively discloses historical nexus and unfiled returns in exchange for a capped lookback period, typically 3 to 4 years depending on the state, and waiver of penalties. Interest on unpaid tax is generally still owed. VDA is the right path when historical exposure is meaningful and the brand has not been formally contacted by the state. For brands that already received a nexus questionnaire, counsel evaluates whether the questionnaire constitutes disqualifying contact, or whether the brand can still initiate VDA before the questionnaire response is filed.
Standard registration with prospective effective date
The brand registers from the date nexus is confirmed, without addressing historical exposure. Prior-period liability remains open for assessment. Standard registration is the right path when historical exposure is genuinely minimal or when counsel determines a defensible position exists that nexus did not apply in prior periods.
Challenge to the nexus position
If the brand believes nexus does not exist, counsel drafts the response to reflect that position with its factual basis. A documented good-faith position is required; a claim without supporting facts is worse than no claim at all.
For brands with a multi-state footprint that includes SST member states, the remediation decision at each state affects the SST enrollment picture. Once a brand resolves historical exposure through VDA and registers in one of the 24 participating SST states, SST filing consolidation is available prospectively. TaxCloud, as one of the program's Certified Service Providers, handles the prospective filing chain across those 24 states through a single consolidated process rather than 24 separate state filings, which is the operational frame the questionnaire response leads into.
Building the documentation chain
Five items form the documentation chain for a nexus questionnaire response. If the response leads to a registration and that registration later leads to an audit, an auditor's first document request will reference this exchange. The strength of the chain limits the state's ability to reconstruct facts in its favor.
1. The original letter, including envelope and postmark
The postmark establishes the letter date and the start of the response clock. The envelope is evidence in any dispute about when the deadline began. Do not discard it.
2. The response draft with counsel's annotations
Even in cases where counsel reviewed only specific questions, preserve the draft showing which sections were reviewed and what changes were made. This documents the decision to route certain questions through counsel and demonstrates good-faith compliance behavior if the response is later scrutinized.
3. The final signed response with all attachments
The completed questionnaire, every data exhibit, and any supporting documentation submitted with the response, preserved in the form filed.
4. The source data exports
Not just the exhibit attached to the form, but the raw export files used to generate the numbers: Shopify's state-level tax or order reports, Amazon Seller Central settlement reports by state, and any other channel data. These support every dollar figure on the form. Store them with the response package as a self-contained audit file.
5. Proof of timely delivery
Certified mail receipt with green card return if mailed. Portal submission confirmation screenshot with timestamp if filed online.
The documentation chain matters beyond the immediate compliance use case. When M&A diligence reviews historical sales tax compliance, this file is what tax counsel requests. When a new controller inherits the function and needs to reconstruct the nexus history, the chain explains what happened, when, and on what basis. When the next questionnaire arrives from a different state, the chain is the operational template.
Once nexus is confirmed and the remediation path is set, the registration and prospective filing chain take over. TaxCloud handles registration across confirmed states, consolidated SST filing across the 24 participating states, and the full documentation trail from calculation records to filing confirmations that an auditor requests. The questionnaire defines the obligation; what follows is the operating model.