Form 1120 preparation for US businesses

A named person on our team owns your file and reviews everything that leaves it. Software does a real share of the grinding underneath it — coding, matching, flagging the obvious gaps — but nothing regulated happens without a person’s judgement, and nothing here is signed or filed by an algorithm.

Prepared with partner CPA firms who review, sign and file; state apportionment judgment is theirs.

Whatever you already run. Most commonly QuickBooks, Xero, NetSuite, Sage, Zoho Books and a handful of others — we work inside your system rather than moving you onto one of our own.

A short, free read-only look at what you already have, and a written note on what we found. A scoping call decides the size of the engagement — nothing here commits you to anything.

There is no published price for form 1120 preparation — it depends on volume, how many entities are involved, and how far behind the books are. We quote after the read-only review, which is free.

Form 1120 preparation sits inside tax filings, alongside Form 1040 preparation, Schedule C & self-employment taxes, Form 1065 & K-1 preparation. Most clients end up buying the category as a whole rather than one leaf at a time, but starting narrow is fine.

Form 1120 is the C-corp return — the corporation pays its own federal tax at a flat 21% rate, and shareholders are taxed again only on dividends actually distributed. Form 1120-S is for a corporation that has filed a valid S-election (Form 2553); there's no entity-level federal tax there, and income passes straight through to shareholders on Schedule K-1. If your corporation has an S-election on file, you want our Form 1120-S leaf instead.

One per state where the corporation is registered to do business or has established nexus — often through employees, property, inventory, or crossing a state's economic-nexus revenue threshold from sales. A corporation registered or operating in three states typically files four corporate returns for one fiscal year: the federal 1120 plus three state returns, each with its own fee, formula, and deadline.

The 15th day of the fourth month after year-end — April 15 for a calendar-year corporation. Form 7004 gives an automatic six-month extension to file, pushing that to October 15. The extension only moves the filing deadline; any tax owed is still due on the original date, and interest starts accruing from there if it isn't paid.

Yes. Form 1120 is required annually regardless of activity level — there's no automatic exemption for a dormant or pre-revenue C-corp. Skipping a zero-income year still leaves a compliance gap that has to be caught up later, so we track the filing calendar every year, not just active ones.

Each state's own apportionment formula — commonly based on sales, property, and payroll in that state versus everywhere the corporation operates, though the exact formula (single-sales-factor, three-factor, or a variant) differs state by state. We build the worksheet with the revenue and location data each state's formula needs; the partner CPA firm determines the actual apportionment position where judgment is required.

The corporation pays tax once on its own income when Form 1120 is filed. If and when it distributes a dividend to shareholders, that distribution is taxed again at the shareholder level. Earnings the corporation keeps and doesn't distribute are only taxed the once, at the entity level — which is why the decision to distribute versus retain is a real planning question, one that sits with the corporation's CPA and board.

The partner CPA firm we work with reviews the finished return, makes the state apportionment call where judgment is required, signs as paid preparer, and files it with the IRS and every applicable state. We prepare the return from your closed books and hand it to them ready for that review, with signing and filing sitting on the partner CPA firm's side of the handoff.

A closed, reconciled trial balance for the fiscal year, your fixed-asset and depreciation records, a list of every state you're registered or operating in, and last year's filed return if this isn't the first year. The cleaner the closed file, the less back-and-forth the CPA review needs.

Tell us about any new employees, contractors, property, or meaningful sales activity in a state you haven't filed in before — we track that against the state's nexus rules and flag it. Whether it actually rises to a filing obligation, and how income gets apportioned to it, is the partner CPA firm's determination.

That's a tax-planning and eligibility question — S-corp status has ownership restrictions (no more than 100 shareholders, US individuals or certain trusts only, one class of stock) and the election itself has IRS deadlines — that belongs with the partner CPA firm. We can prepare either return once the election status is settled.

Interest starts accruing from the original due date on whatever balance is unpaid, and a late-payment penalty can apply if the shortfall is significant, regardless of whether Form 7004 was filed on time. That's why we build a good-faith liability estimate before the original deadline every year an extension is used — so the payment goes in on time even though the paperwork follows later.