Once your US LLC starts invoicing US customers, you'll be asked for a tax form within the first month. Which form depends on your entity type, and the form has a phone field that confuses non-resident founders. This article covers what to put there for each variant.
Which Form Applies to You
The choice between W-9 and W-8BEN-E depends on your entity's US tax classification, not on where you personally live.
| Your Entity | Form You Send | Why |
|---|---|---|
| US LLC (single-member, you're non-resident, not elected corporate) | W-8BEN-E (technically — see below) or W-9 (commonly accepted in practice) | The LLC is "disregarded" for US tax — the form depends on whether the requester treats the LLC as a US entity or pierces to the foreign owner |
| US LLC electing C-Corp status | W-9 | Treated as a US corporation |
| US C-Corp (Delaware C-Corp) | W-9 | US corporation, regardless of who owns it |
| US LLC owned by a non-US entity | W-8BEN-E for the non-US owner | The disregarded LLC's tax form depends on the foreign parent |
The most common case for Stripe Atlas / doola / Firstbase founders is a US C-Corp (Atlas's default for most countries) or a single-member LLC elected to be taxed as a C-Corp. In both cases, the answer is W-9.
Single-member LLCs that did not elect corporate status fall into a more complicated zone. Most US payers will accept a W-9 with the LLC as the payee; some payers (especially banks and larger vendors with sophisticated tax teams) will insist on W-8BEN-E because they're paying the foreign owner, not the disregarded entity. Either way, the phone field works the same.
W-9 Phone Field
Form W-9 is a single page. The phone field — labeled "Requester's name and address (optional)" — is actually for the requester's phone in the official IRS layout, not the taxpayer's. However, many businesses use modified W-9 templates that add a phone line for the taxpayer.
In practice, when a US customer or platform asks you to fill out a W-9, they often include a phone field for you (the LLC/C-Corp) somewhere on the form or in a wrapping signup flow. Use your US company phone for this field. Same number that's on the EIN application, on your Stripe profile, and on every other document for the entity.
What the phone is used for on W-9:
- The customer's tax/finance team may call if your taxpayer ID number doesn't match IRS records (a "B-Notice" — IRS sends one if names and EINs don't match)
- The customer's procurement team may call to verify the vendor
- Year-end 1099 issuance: if there's a problem mailing the 1099 to the address on file, they may try the phone
Like SS-4, the IRS does not check the W-9 phone against any VoIP detection. Any reachable US phone — a $7/month number-on-file service, a $19/month business phone, a US mobile carrier line — all work equally for this purpose.
W-8BEN-E Phone Field
Form W-8BEN-E is the "Certificate of Status of Beneficial Owner for United States Tax Withholding and Reporting (Entities)". It's a more involved form than W-9 — typically 8 pages — used when a foreign entity is the beneficial owner of US-source income.
Part I, line 7 of W-8BEN-E asks for "Mailing address" and elsewhere has fields for "Permanent residence address" and reference numbers. There's no explicit "phone number of beneficial owner" field on the standard IRS form.
That said, many US payers add a phone field in their own W-8BEN-E intake form. If your customer's wrapping form has a phone field, put your foreign company's phone there (or, if you're treating your US LLC as the disregarded entity owner of the foreign parent's income, the US phone associated with that LLC).
In practice for non-resident founders running US LLCs, the W-9 path is more common than W-8BEN-E. When in doubt, ask the requester which form they want you to submit. Many customers' AP teams will accept either if they understand your structure; some will insist on a specific one.
1099 Phone Field
A 1099 is issued to you by a US payer at year-end if they paid you $600 or more in non-employee compensation (1099-NEC) or in certain other categories (1099-MISC, etc.). You don't fill out a 1099 — the payer does, using the info you provided on your W-9.
The phone the payer puts on the 1099 for you is whatever you provided on the W-9 (or in their vendor intake form). If you used your US business phone consistently, the 1099 will have the right phone. If the W-9 phone was inconsistent with your other records, you may receive 1099s addressed with a different phone than the one on Stripe Atlas, and reconciliation gets messier.
Practical Phone Setup for Tax Forms
The cleanest setup for a non-resident founder of a US entity:
- One US phone number that lives on the W-9 template, the EIN documentation, the Stripe Atlas dashboard, and your business email signature.
- Pre-filled W-9 PDF with company legal name, EIN, address, classification (LLC/C-Corp), and phone. Saved in your shared drive.
- Send the same PDF every time a customer asks for a W-9. Don't fill in fresh each time — that's how phone numbers drift over the years.
What I'd Personally Recommend (Based on What Works)
For the phone field across all your tax forms:
- If you're going to actually call US customers and want a business phone with a real app — Quo (formerly OpenPhone) at $15-$19/month.
- If you just need a number that exists on tax forms and gets SMS forwarded to email — IncNumber at $7/month.
The W-9 phone field works equally for both. The choice is about the rest of your business — calling, multi-user, integrations — not about W-9 compliance.
A US phone that lives on all your tax forms
IncNumber is $7/month. Same number stays with your US entity. SMS forwarded to email. No app needed.
Get your US number →Common Mistakes
Mistake 1: Different phone on every W-9
Customer A's W-9 has phone X. Customer B's has phone Y. Customer C's has phone Z. When the IRS does cross-reference (which happens for entities with multiple 1099s), the inconsistency raises questions.
Fix: Save one canonical W-9 PDF and use it everywhere.
Mistake 2: Using your personal home-country mobile
You're a non-resident; your personal number is in your home country. Putting that on a W-9 isn't technically wrong, but it signals "this is a foreign founder, not a US business" to the customer's AP team. Some teams will flag it for additional review.
Fix: Use a US number. Costs $7-$19/month, eliminates the friction.
Mistake 3: Listing the registered agent's phone
You think the registered agent's number is more "official". It isn't, for W-9 purposes. The registered agent is your legal-document recipient, not your tax/business phone.
Fix: Use your own US business phone.
Mistake 4: Phone disconnected mid-year
You used a virtual phone for the W-9, then cancelled it after the deal closed. Six months later, customer's AP team needs to verify before sending payment for a different contract — and the number doesn't work.
Fix: Keep the same US number for the life of the entity. The recurring $7-$19/month is cheaper than the friction of fixing things later.
Bottom Line
W-9 is the form most non-resident founders of US LLCs / C-Corps actually send. W-8BEN-E applies in a narrower set of cases. Both forms work with any real US phone in the phone field — there's no VoIP detection at the IRS or at standard US business customers.
Pick one US phone, put it on every form, keep it active for the life of the entity. That single decision eliminates 90% of the W-9 / 1099 friction non-resident founders run into.