Paying Subs: W-9s, 1099-NEC and Backup Withholding

The W-9 comes before the first check, not with the last one. Form W-9 is how you collect a subcontractor’s legal name, entity type and taxpayer identification number, and everything downstream runs off it: whether you owe a 1099-NEC at all, whose name goes on it, and whether you have to withhold from the payment before it leaves your account. Collecting it in January from a sub who finished in March and has stopped returning calls is the avoidable version of this job.

Why it matters on the job

You have leverage over a sub exactly as long as you still owe them money. The W-9 costs nothing to obtain at that moment and becomes very difficult afterward. Treat it as part of setting up the vendor, filed alongside their certificate of insurance and their license number, and the January filing turns into a report you run rather than a hunt you conduct.

What the W-9 collects, and why each field is there

• Legal name, plus the business name if it differs. The IRS matches the name to the number. A check made out to “Ridgeline Framing” filed under an owner’s Social Security number is how mismatch notices start.
• Federal tax classification. Sole proprietor, partnership, C corporation, S corporation, or LLC and how that LLC is taxed. This field can decide whether a payment is reportable at all, because the exceptions in the Form 1099-NEC instructions are drawn by payee type.
• The taxpayer identification number, an SSN or an EIN.
• A signed certification that the number is correct and that the payee is not subject to backup withholding.

You do not send the W-9 anywhere. It stays in your file as the evidence behind whatever you file later, and as your defense if a number turns out to be wrong.

What the 1099-NEC reports, and the number that moved

Form 1099-NEC reports nonemployee compensation: payments made in the course of your trade or business, to someone who is not your employee, for services. For a builder that is most of the sub ledger.

For tax years beginning after 2025, the reporting threshold for nonemployee compensation is $2,000. For 2025 and earlier tax years the threshold was $600, and beginning with calendar year 2027 the $2,000 figure is indexed for inflation.

Both numbers are correct about their own tax year, which is why neither one should be written down without its year attached. Guidance published before the change still describes the $600 rule, and so may your accounting software: a package configured in 2024 is still testing your subs against $600.

Two properties of the threshold catch contractors out.

It is an annual total per payee, not a per-payment test. Four progress payments of $700 to the same framer total $2,800, and $2,800 is what meets the threshold. Nothing about a single $700 check tells you what you will owe in January.

It is a floor under the filing, not under the payment. A sub you paid $1,400 is still a business expense, still belongs in your job costing, and still needs a W-9 in the file, because in March you had no way of knowing what December would total.

Backup withholding

Backup withholding is what makes the W-9 worth chasing rather than merely tidy. If a payee does not furnish a correct taxpayer identification number, or the IRS notifies you that the number you filed does not match its records, you are required to withhold federal income tax from the payments, remit what you withheld, and report it on the 1099-NEC. That obligation lands on you as the payer, not on the sub. The sub is not out the money in the end (it is credited against their own tax), but they are out the cash flow, and you have acquired a withholding, depositing and reporting job you did not price into the contract.

The current rate and the notice sequence come from the Form 1099-NEC instructions and the IRS backup-withholding guidance, and neither is reproduced here, because a stale withholding rate is a penalty with your name on it. The structural point is the one to carry onto the job: no valid TIN can mean you must withhold, and the way to avoid that entirely is to have the W-9 in hand before the first payment.

Worked example: three subs, one tax year

Your books for a tax year beginning in 2026 show three subcontractors, all sole proprietors, all with W-9s on file.

• Trim carpenter. $850 in April, $1,400 in July, $600 in October. Annual total: $850 + $1,400 + $600 = $2,850.
• Final-clean crew. $900 in May, $600 in September. Annual total: $900 + $600 = $1,500.
• Excavator. One payment of $2,400 in March.

Test each annual total against $2,000, the threshold for tax years beginning after 2025.

1. Trim carpenter, $2,850: over the threshold. File a 1099-NEC.
2. Excavator, $2,400: over the threshold on a single payment. File a 1099-NEC.
3. Final-clean crew, $1,500: under. No 1099-NEC for this tax year.

The annual total is what meets the line, and no single payment tells you where the year will land

Now look at what moved. Under the $600 threshold that governed 2025 and earlier, all three of these subs cleared it and all three got a form. The clean crew’s $1,500 is the same $1,500 it would have been in either year: the threshold moved, not the payment. That is the entire reason to write the tax year beside the number.

Look also at what did not move. The clean crew’s W-9 is still in your file, their $1,500 is still in your job costs, and if they run to $3,000 with you next year, you already hold everything you need to file.

When the classification itself is the question

Everything above assumes the payee really is a subcontractor: someone whose work you direct as to the result, not as to the means and methods of getting there. That determination is made by the tests in Employee vs Subcontractor Classification, and the 1099-NEC follows the determination rather than making it.

Where you and the worker genuinely cannot tell, either of you can file Form SS-8 and ask the IRS to determine the worker’s status for federal employment tax purposes. The determination settles that one relationship and does not become a rule you can carry to the next hire. And if the answer is employee, you are in a different regime entirely: withholding, the employer’s share of employment taxes, and FUTA, on their own calendars with their own filings.

Where it bites

• The 1099-NEC is a report, not a ruling. Filing one does not turn a worker into a subcontractor, and skipping one does not turn them into an employee. It records a payment that was already made under a status that was already determined.
• A hundred dollars can be the whole difference. A sub at $1,950 and a sub at $2,050 are $100 apart and one filing obligation apart. Your books decide which side of the line they landed on, and February is a bad month to be reconstructing that from check stubs.
• Entity type can change the answer. The 1099-NEC instructions draw their exceptions by payee type, so an LLC’s tax election can move a payee in or out of scope. That is a question for the current instructions or your CPA, answered per payee, and never a rule of thumb carried between jobs.
• Mixed invoices are an instructions question. A sub who bills labor and materials on one invoice raises a real question about what amount is reportable. Look it up for that year rather than deciding it on the job.

The habit that makes all of this cheap fits in one line of your vendor setup: no W-9, no first payment. Every problem above starts with skipping it.