Line 1: Partnership's U.S. EINA partnership without an EIN must get one and still pay on time. If the EIN has not arrived when the voucher is filed, enter the date the partnership applied, then send the EIN to the IRS at the Ogden address on receipt. A missing EIN can delay crediting payments to partners.Click to open the row in the table belowLine 2: Amount of this paymentThe installment figured for all foreign partners under the principles of section 6655 and Treas. Reg. 1.1446-3, using Form 8804-W.Click to open the row in the table belowLine 3: Partnership's name and addressName, street, room or suite, city, state and ZIP code. Use a P.O. box only if mail is not delivered to the street; for a foreign address, give the full country name and follow its postal code practice.Click to open the row in the table belowHover over a line for what goes on it; click to open its row in the table below. On a touch screen, tap the line to jump to the row.
Who files Form 8813
A partnership (other than a PTP) with ECTI allocable to foreign partners pays section 1446 tax in four installments during its tax year, and “Form 8813 must accompany each payment of section 1446 tax made during the partnership's tax year.” Payments can also be made through EFTPS instead of by check or money order. Either way, Forms 8804 and 8805 must still be filed, and Form 8813 “as applicable”.
A voucher can be required with no payment. If an installment was reduced for a partner's state and local income taxes under Treas. Reg. 1.1446-6(c)(1)Treas. Reg. 1.1446-6Treasury regulations, Cornell LII(iii), or by relying on a partner's Form 8804-C, the documentation goes with every Form 8813 from the first period the certificate was considered, and “a partnership must file Form 8813 for an installment period even if no section 1446 withholding tax is due.”
When it pays an installment, the partnership must tell each foreign partner its share within 10 days of the due date (or the payment date, if paid). Payments are reported for the year on line 6a of Form 8804 and credited to partners on Form 8805.
Line by line
| Line | What it is | Notes |
|---|---|---|
| Header | Tax year | Calendar year or fiscal year dates of the partnership tax year the payment is for. |
| 1 | Partnership's U.S. EIN | A partnership without an EIN must get one and still pay on time. If the EIN has not arrived when the voucher is filed, enter the date the partnership applied, then send the EIN to the IRS at the Ogden address on receipt. A missing EIN can delay crediting payments to partners. |
| 2 | Amount of this payment | The installment figured for all foreign partners under the principles of section 6655 and Treas. Reg. 1.1446-3, using Form 8804-W. |
| 3 | Partnership's name and address | Name, street, room or suite, city, state and ZIP code. Use a P.O. box only if mail is not delivered to the street; for a foreign address, give the full country name and follow its postal code practice. |
Due dates
| What | Due | Notes |
|---|---|---|
| 1st installment for 2026 (calendar year) | April 15, 2026 | 15th day of the 4th month of the tax year. |
| 2nd installment | June 15, 2026 | 15th day of the 6th month. |
| 3rd installment | September 15, 2026 | 15th day of the 9th month. |
| 4th installment | December 15, 2026 | 15th day of the 12th month. |
| Partner notification | Within 10 days of each due date or payment date | Required notice of each foreign partner's share. |
| Balance of 2026 tax | March 15, 2027 | Paid with Form 8804, or with Form 7004 if filing for an extension. |
| 1st installment for 2027 (calendar year) | April 15, 2027 | Use the 2027 Form 8804-W. |
Deposits
Figuring the installment. Each installment is the sum of the installments for each foreign partner, figured under the principles of section 6655 and Treas. Reg. 1.1446-3 on Form 8804-W, a worksheet kept with the partnership's records and not filed. The worksheet multiplies expected ECTI by the same rates as Form 8804: 21% for corporate partners, 37% for non-corporate ordinary income, and 28%, 25% or 20% for documented preferential-rate gain. It generally requires 25% of the annual amount each quarter. The annualized income method and the adjusted seasonal method (only if the base period percentage for any 6 consecutive months is at least 70%) can lower an installment. A prior-year amount can apply only if certain conditions are met.
De minimis. “If the aggregate line 7 amount of all foreign partners is less than $500, the partnership is not required to make estimated tax payments.” (Form 8804-W, 2026.)
Paying. Mail the voucher with a check or money order payable to the “United States Treasury” with the partnership's EIN, the tax year and “Form 8813” on the check. “Do not staple or attach this voucher to your payment.” The IRS recommends paying electronically; EFTPS can be used instead.
Attachments. If an installment was reduced because the partnership relied on Forms 8804-C, attach those forms and a statement showing the tax calculation for each such partner. If it was reduced for state and local taxes, attach a calculation. One statement can cover both. A Form 8804-C reused in a later period can be handled under the substitute in Treas. Reg. 1.1446-6(d)(3)(i)Treas. Reg. 1.1446-6Treasury regulations, Cornell LII.
Penalties
Missing or short installments draw a penalty figured on Schedule A (Form 8804) and entered on Form 8804 line 8. If no Schedule A is attached, the IRS figures the penalty without regard to the exceptions on the schedule. If the 2026 Form 8804-W line 7 amount is used for an installment when it is smaller than the line 8 prior-year amount, the partnership does not qualify for the prior-year safe harbor on Schedule A.
A person required to withhold and pay over section 1446 tax who fails to do so can face the section 6672 civil penalty, equal to the amount that should have been paid over. Interest applies to tax not paid by the due date.
A partnership that relied on a W-8 or W-9 is not penalized for failing to pay before it knows or has reason to know the certificate is invalid, but it is liable for the tax, penalties and interest starting with the installment period in which it knew or had reason to know.
Corrections
The instructions provide no amended Form 8813. A short installment is made up by a later payment, and the year is settled on Form 8804: all installments are reported on line 6a, any balance is paid on line 10, and an overpayment can be allocated to partners, refunded or credited to next year.
Where it goes wrong
- Waiting until year end. Section 1446 tax is due in four installments during the tax year, whether or not the partnership makes distributions.
- No voucher when a certificate cut the tax to zero. After relying on Form 8804-C or the state and local tax reduction, file Form 8813 for the period with the documentation, even with no payment.
- No EIN on the voucher. Get the EIN; if it is pending, enter the application date on line 1 and send the EIN to the IRS when received.
- Stapling or sending cash. The voucher says “Do not send cash.” and not to staple or attach the voucher to the payment.
- Partners not told. Each foreign partner must be told its share within 10 days so it can adjust its own estimated tax.
Questions people ask about Form 8813
Do we need Form 8813 if we pay through EFTPS?
The instructions say payments may be sent through EFTPS instead of a check or money order, and that Forms 8804 and 8805 must still be filed “(and 8813, as applicable)”. Form 8813 is still required for a period in which an 8804-C or state tax reduction was used, even with no payment.
When are the 2026 installments due for a calendar-year partnership?
April 15, June 15, September 15 and December 15, 2026.
Is there a minimum below which we do not pay installments?
Yes. The 2026 Form 8804-W says no estimated tax payments are required if the aggregate line 7 amount for all foreign partners is less than $500.
What do we attach to Form 8813?
Any Forms 8804-C the partnership relied on, with a statement of the tax calculation for each such partner, and a calculation of any state and local tax reduction. The voucher itself is not stapled to the check.
Can a foreign partner get an early refund of an installment?
No. The partner claims the tax as a credit on its own return using Form 8805, and cannot claim an early refund of section 1446 tax.
Other employer, withholding and ACA forms
Payroll and employment tax returns: W-4 · 941 · 941-X · 944 · 943 · 940 · W-2 · W-3 · W-2c · 8027
Withholding returns: 945
Foreign withholding and FATCA returns: 1042 · 1042-T · 8966 · 8804 · 8805 · 8288 · 8288-A
Health coverage (ACA) returns: 1095-C · 1094-C · 1095-B · 1094-B
Paper transmittal: 1096
These forms on the comparison table · Information returns (1099 series)
Sources: Form 8813 (Rev. December 2026); Instructions for Forms 8804, 8805, and 8813 (Rev. January 2026); Form 8804-W (2026 and 2027); IRS page About Form 8813.