CORPORATION TAX RETURN
Corporation tax returns: Form 1120 and 1120-S
A C-corporation files Form 1120 and pays 21% federal tax on its profit; an S-corporation files Form 1120-S and its profit is taxed on the owners' personal returns. We prepare both, including Form 5472 when a foreign owner holds 25% or more.
Which one is yours? (H2, two columns)
Form 1120: C-corporations. For corporations and LLCs that elected to be taxed as one, with owners anywhere. Tax: 21% of taxable profit. If a foreign person or company owns 25% or more, Form 5472 is attached, and we include it. Dividends paid to foreign owners usually carry 30% US withholding, or a lower treaty rate.
Form 1120-S: S-corporations. Only for companies whose owners are all US citizens or residents. The company usually pays no federal income tax; each owner reports their share from a K-1 on their own Form 1040. Owners who work in the business take a reasonable salary through payroll.
Important: a non-US resident can't own shares in an S-corporation. If an owner moves abroad and becomes a non-resident, S status ends automatically on that day. Tell us early; we'll explain the options.
Thinking about an S-corp election? An S-corp saves tax only above a certain profit, and the right level depends on your numbers. We calculate it for you in writing before you decide.
Published 9 November 2026 · Reviewed by Ishfaq Ahmed, IRS Certifying Acceptance Agent
What's included
- Form 1120 or Form 1120-S, with the required schedules
- Form 5472 for each 25% foreign owner (Form 1120)
- Schedule K-1 for each shareholder (Form 1120-S)
- Drafts in your portal to approve, and revisions until they're right
- E-filing with the IRS and the acknowledgement in your portal
Not included (quoted separately): payroll filings, state corporate returns, Delaware franchise tax and other state reports (see Annual reports), and shareholders' personal returns (Form 1040).
How it works
- Start in the portal. Create your account, choose the service, accept the client agreement and get your invoice. 2. Send your documents. Upload them in the portal (not by WhatsApp or email). We tell you if anything is missing. 3. We prepare your draft. Our preparer builds the return in professional tax software. 4. You check and approve it. You get the draft in the portal. Approve it, or ask for a change and we send a new version. 5. Pay and sign. Full payment before we file. Then print Form 8879 (the form that lets us e-file for you), sign it with a pen and upload a clear photo or scan. 6. We file and send proof. Ishfaq Ahmed reviews and files every return. We e-file it with the IRS, and the IRS acknowledgement goes into your portal with your final copy., with step 5 line: "Then an officer of the company prints Form 8879-CORP (or 8879-S), signs it with a pen and uploads a clear scan." Then Our cut-off: send your documents, approval, signature and payment by the 13th of the deadline month (13 March, 13 April, 13 June). After that we file an extension first ($50, a separate service) and then your return.
What we need from you
- The tax year
- Company details and EIN letter
- Each shareholder and their percentage
- An income statement, or the year's bank statements
- Total assets at December 31
- Whether the company ran payroll
- Any transactions with owners or related companies
- Last year's return, if one was filed
Deadlines and penalties
- Form 1120-S: March 15, 2027; extension to September 15, 2027.
- Form 1120: April 15, 2027; extension to October 15, 2027.
- Extensions (Form 7004) must be filed by the original due date and give more time to file, not to pay. Tax extensions, $50.
- Late Form 1120-S: $260 per shareholder for each month late, up to 12 months (returns due in 2027).
- Late Form 1120 with tax owed: 5% of the unpaid tax per month, up to 25%.
- Missing Form 5472 inside a Form 1120: $25,000.
Price
$449 per tax year, for either Form 1120 or Form 1120-S. Full payment before we file. Bank transfer; the payment details come with your invoice in the portal. Card payments are not available yet. The IRS charges nothing to file a return; our fee is for preparing and filing it.
Frequently asked questions
What's the federal tax rate for a C-corporation?
21% of taxable profit. States may add their own tax.
Can I, as a non-US resident, own an S-corporation?
No. Every S-corp shareholder must be a US citizen or resident. A C-corporation works for owners anywhere.
My LLC elected to be a C-corp. Which return?
Form 1120, the same as any corporation.
Is Form 5472 included?
Yes, when a foreign owner holds 25% or more and there were transactions between them and the company.
Does an S-corp always save tax?
No. It depends on your profit, the salary you take and the extra costs. We calculate it in writing first.
Do you handle Delaware franchise tax?
Yes, as a separate state filing. See Annual reports.