(Rev. December 2025)

Instructions for

Form 4466

(Rev. December 2025)

Corporation Application for Quick Refund of Overpayment of Estimated Tax

Section references are to the Internal Revenue Code

unless otherwise noted.

Future Developments

For the latest information about developments affecting

Form 4466 and its instructions, such as legislation

enacted after they were published, go to IRS.gov/

Form4466.

What’s New

Electronic payments. If the corporation has access to

U.S. banking services or electronic payment systems, it

should use direct deposit for any refunds and pay

electronically for any payments, whenever possible.

Direct deposit. Direct deposit fields have been added

to this form on lines 8b, 8c, and 8d. For the overpayment

of estimated tax on line 8a, enter the corporation’s direct

deposit information on lines 8b, 8c, and 8d. See Line 8a,

later.

General Instructions

Who May File

Any corporation that overpaid its estimated tax for the tax

year may apply for a quick refund if the overpayment is:

• At least 10% of the expected tax liability; and

• At least $500.

The overpayment is the excess of the estimated

income tax the corporation paid during the tax year over

the final income tax liability expected for the tax year, at

the time this application is filed.

If members of an affiliated group paid their estimated

income tax on a consolidated basis or expect to file a

consolidated return for the tax year, only the common

parent corporation may file Form 4466.

If any member of the group paid estimated income tax

during the portion of the tax year when it was not a

member, the member (and not the common parent) must

file the Form 4466 to request a quick refund of any

estimated tax overpayment it made in that portion of the

year.

Note: Form 4466 is not considered a claim for credit or

refund.

When To File

File Form 4466 after the end of the corporation’s tax year,

and no later than the due date for filing the corporation’s

tax return (not including extensions). Form 4466 must be

filed before the corporation files its tax return. An

extension of time to file the corporation’s tax return will not

Jan 20, 2026

extend the time for filing Form 4466. See the instructions

for the corporation’s tax return.

How To File

Complete and file an original, signed Form 4466 with the

applicable Internal Revenue Service Center (see Where

To File below). The IRS will act on Form 4466 within 45

days from the date it is filed.

The corporation must also file Form 4466 with its

income tax return. Attach either the signed Form 4466 or

an unsigned Form 4466 with the same information stated

on the signed Form 4466. If the corporation submits an

unsigned Form 4466, it must retain the original, signed

Form 4466 in its records.

Disallowance of application. Any application that

contains material omissions or errors that cannot be

corrected within the 45-day period may be disallowed.

Where To File

File Form 4466 at the applicable address listed below.

Filers of...

Use the following address:

Form 1120-F or 1120-FSC, or the Internal Revenue Service Center

corporation’s principal business,

P.O. Box 409101

office, or agency is located in a

Ogden, UT 84409

foreign country or U.S. possession

Forms 990-T, 1120, 1120-C,

1120-H, 1120-L, 1120-ND,

1120-REIT, 1120-RIC, 1120-PC,

or 1120-SF

Department of the Treasury

Internal Revenue Service Center

Ogden, UT 84201

Specific Instructions

Address

If the post office does not deliver mail to the street address

and the corporation has a P.O. box, show the box number

instead.

Note: If a change in address occurs after the corporation

files Form 4466, use Form 8822-B, Change of Address or

Responsible Party — Business, to notify the IRS of the

new address.

Type of Return

Check the box for the type of return the corporation will

file.

Other. S corporations that have made protective

estimated tax payments in their first tax year should check

the “Other” box. Corporations that file Forms 1120-FSC,

1120-H, 1120-ND, 1120-REIT, 1120-RIC, or 1120-SF and

Instructions for Form 4466 (Rev. 12-2025) Catalog Number 95870U

Department of the Treasury Internal Revenue Service www.irs.gov

tax-exempt corporations that file Form 990-T should also

check the “Other” box. Enter the form number of the return

to be filed in the space to the right of the box.

Line 4.

Enter the total tax from Form 1120, Schedule J, or the total

tax from your applicable tax return. See the instructions for

your applicable tax return.

Line 8a. Overpayment of Estimated

Tax

If the application for refund is approved, the overpayment

on line 8a may be credited against any tax the corporation

owes. The balance, if any, will be refunded. If the

corporation has access to U.S. banking services, it should

use direct deposit for any refunds, whenever possible. The

benefits of a direct deposit include a faster refund, the

added security of a paperless payment, and the savings of

tax dollars associated with the reduced processing costs.

Direct deposit. If the corporation wants its refund directly

deposited into its checking or savings account at any U.S.

bank or other financial institution, complete lines 8b

through 8d. See the instructions for lines 8b, 8c, and 8d,

later.

The corporation is not eligible to request a direct

deposit if:

• The receiving financial institution is a foreign bank or a

foreign branch of a U.S. bank; or

• The corporation has applied for an EIN but is filing its

tax return before receiving one.

Line 8b. Routing number. The routing number must be

nine digits. The first two digits must be 01 through 12 or 21

through 32. Ask the corporation’s financial institution for

the correct routing number to enter on line 8b if:

• The routing number on a deposit slip is different from

the routing number on the corporation’s checks;

• The deposit is to a savings account that does not allow

you to write checks; or

• The corporation’s checks state they are payable through

a financial institution different from the one at which the

corporation has its checking account.

Line 8c. Type of account. Check the appropriate box for

the type of account. Don’t check more than one box. The

corporation must check the correct box to ensure your

deposit is accepted.

Line 8d. Account number. The account number can be

up to 17 characters (both numbers and letters). Include

hyphens but omit spaces and special symbols. Enter the

number from left to right and leave any unused boxes

blank. Don’t include the check number.

If the direct deposit to the corporation’s account is

different from the amount expected, the corporation will

receive an explanation in the mail about 2 weeks after the

refund is deposited.

Conditions resulting in a refund by check. If the IRS is

unable to process the request for a direct deposit, a refund

by check will be generated instead. Reasons for not

processing a request include.

• The name of the corporation on the tax return does not

match the name on the account.

2

• The financial institution rejects the direct deposit

because of an incorrect routing or account number.

• The corporation fails to indicate the type of account the

deposit is to be made to (that is, checking or savings).

Note: The IRS is not responsible for a lost refund if the

corporation enters the wrong account information. Check

with the corporation’s financial institution to get the correct

routing and account numbers and to make sure the direct

deposit will be accepted.

Excessive refund or credit. If the refund or credit is later

found to be excessive, the corporation is liable for an

addition to tax on the excessive amount. See section

6655(h).

The excessive amount is the smaller of:

1. The credit or refund; or

2. The excess of:

a. The corporation’s income tax liability (as defined in

section 6425(c)) as shown on its return over

b. The estimated tax paid less the refund or credit.

The IRS will figure the addition to tax and bill the

corporation.

The addition to tax is figured from the date the refund

was paid or credited, until the original due date of the

corporation’s return. The addition to tax is not deductible

for income tax purposes.

Paperwork Reduction Act Notice. We ask for the

information on this form to carry out the Internal Revenue

laws of the United States. You are required to give us the

information. We need it to ensure that you are complying

with these laws and to allow us to figure and collect the

right amount of tax.

You are not required to provide the information

requested on a form that is subject to the Paperwork

Reduction Act unless the form displays a valid OMB

control number. Books or records relating to a form or its

instructions must be retained as long as their contents

may become material in the administration of any Internal

Revenue law. Generally, tax returns and return information

are confidential, as required by section 6103.

The time needed to complete and file this form will vary

depending on individual circumstances. The estimated

burden for business taxpayers filing this form is approved

under OMB control number 1545-0123 and is included in

the estimates shown in the instructions for their business

income tax return.

If you have comments concerning the accuracy of

these time estimates or suggestions for making this form

simpler, we would be happy to hear from you. You can

send your comments to IRS.gov/FormComments. Or you

can send your comments to the Internal Revenue Service,

Tax Forms and Publications, 1111 Constitution Ave. NW,

IR-6526, Washington, DC 20224. Do not send the form to

this address. Instead, see Where To File, earlier.

Instructions for Form 4466 (Rev. 12-2025)