EXTREME US Corporate Tax Returns — 1120, 1120-S & 1065 Prepared Properly
Annual federal tax returns for US companies — C-corps, eligible S-corps, partnerships and foreign-owned LLCs — with state returns where required. The right form, prepared properly and filed on time, 100% online.
What Are US Corporate Tax Returns?
Corporate tax returns are the annual federal returns a US company files with the IRS: Form 1120 for C-corporations, Form 1120-S for S-corporations, and Form 1065 for partnerships — plus state returns wherever your company is required to file them.
Getting the right form matters more than most founders realize. A foreign-owned single-member LLC is a disregarded entity for US tax — it does not file a partnership return; it files a pro-forma Form 1120 with Form 5472 attached (see our Form 5472 service for the full breakdown). And one critical IRS rule: a non-resident alien cannot be a shareholder of an S-corporation — 1120-S is only for eligible US-owned corporations. Filing the wrong form is one of the most expensive mistakes a new company can make, and it is entirely avoidable.
Who Needs Corporate Tax Return Preparation?
If your company exists on paper, it almost certainly has a filing obligation — even with zero income:
- C-corporations filing Form 1120 — including non-resident-owned C-corps. See our C-Corp Formation service if the entity itself is not set up yet.
- Eligible US-owned S-corporations filing 1120-S — remember: non-resident aliens cannot elect or hold S-corp status under IRS rules.
- Partnerships and multi-member LLCs filing Form 1065 — information returns that pass income through to the partners.
- Foreign-owned single-member LLCs — pro-forma 1120 + Form 5472, even when the LLC had no US income. See our Form 5472 service.
- Companies with state filing obligations — federal and state returns assessed together, so nothing falls between them.
- Founders whose books are behind — we review what you have and prepare from there. Our Bookkeeping service can clean the records up first if needed.
What’s Included in Our Tax Return Preparation
From books review to filed return — with a summary you actually understand:
Books Review + Return Preparation
We review your books and prepare the return accurately for your entity type — no copy-paste, no wrong-form filing.
Federal + State Returns
Your federal return plus state returns where your company is required to file them, handled together.
Extension Filing Where Needed
If your records need more time, we file for an extension where needed so you avoid late-filing penalties while everything is completed properly.
E-Filing Where Available
Returns are filed electronically wherever the IRS and the state allow it — faster, trackable and receipted.
Plain-English Summary
You get a clear summary of what was filed and why, in plain English — so you actually understand your own return.
Closing the company instead of filing again? See our Company Dissolution service — and keep your yearly Annual Reports current either way, because a lapsed company still owes its filings.
How Corporate Tax Return Preparation Works — in 4 Steps
Send your books + company details
Message us on WhatsApp with your entity type, ownership, tax year and whatever books or records you have.
We confirm the correct form
1120, 1120-S, 1065 or pro-forma 1120 + 5472 — we determine the right filing for your entity and ownership before anything is prepared.
We prepare + review with you
The return is prepared from your records and reviewed with you, so you sign off on numbers you understand.
We file + summarize
E-filed where available, with a plain-English summary of what was filed and any deadlines you need to track next.
1120 vs. 1120-S vs. 1065 vs. 5472 — Who Files What
The single most common source of expensive mistakes in US company tax. Read this before you assume your form:
- Form 1120 — C-corporations. The standard corporate income tax return.
- Form 1120-S — S-corporations ONLY, and IRS rules require every S-corp shareholder to be a US citizen or resident. Non-resident aliens cannot own or elect an S-corporation. Full stop.
- Form 1065 — Partnerships, including multi-member LLCs taxed as partnerships. An information return; income passes through to the partners.
- Pro-forma 1120 + Form 5472 — foreign-owned single-member LLCs (disregarded entities). Even with zero US income. See our Form 5472 service for the full breakdown.
Not sure which one you are? Tell us your entity type and ownership on WhatsApp — we put you on the right form before anything is filed, because fixing a wrong filing costs far more than getting it right the first time.
Corporate Tax Returns — Frequently Asked Questions
Which tax form does my company file?
It depends on your entity type and tax election: a C-corporation files Form 1120; an eligible US-owned S-corporation files Form 1120-S; a partnership or multi-member LLC taxed as a partnership files Form 1065; and a foreign-owned single-member LLC files a pro-forma Form 1120 with Form 5472 attached. Tell us your entity and ownership and we confirm the right form before anything is filed.
Can a non-resident own an S-corporation?
No. IRS rules require every S-corporation shareholder to be a US citizen or resident. A non-resident alien cannot hold S-corp shares and cannot elect S-corp status. If someone told you otherwise, talk to us before you file.
What does a foreign-owned single-member LLC file?
A foreign-owned single-member LLC is a disregarded entity for US tax purposes. It files a pro-forma Form 1120 with Form 5472 attached, reporting reportable transactions with its foreign owner. See our Form 5472 service for the full breakdown.
When are corporate tax returns due?
Deadlines vary by entity type and tax year, and extensions are available. Tell us your entity type and tax year and we will confirm your deadline and file any extension needed so you do not face late-filing penalties.
Do you handle state tax returns as well?
Yes, where your company is required to file them. Federal and state obligations are assessed together, so nothing slips through the gap between the two.
How much does tax return preparation cost?
It depends on your entity type, how many states are involved and the state of your books. Message us on WhatsApp with those details and we will share the exact price.
Get the Right Form Filed — the First Time
Send us your entity type, ownership and tax year on WhatsApp — we will confirm the correct form, tell you what we need from you and share the exact price. No prices are listed here because every return depends on entity, states and books.
Chat on WhatsApp — Get Price