Your S-corporation passes income through.
An S-corporation generally pays no federal income tax itself. Instead it files Form 1120-S to report its income and hands each owner a Schedule K-1 for their share, which they report on their personal return. It is how S-corporations avoid the double taxation of a C-corporation. We prepare the return, issue the K-1s, and file on time.
An information return, not a tax bill for the company.
Form 1120-S is the annual return of an S-corporation. The important thing about it is what it does not do: an S-corporation generally pays no federal income tax at the entity level. Instead, the return reports the company's income, deductions, and credits, and then allocates each shareholder their share on a Schedule K-1. The shareholders report those amounts on their personal returns and pay the tax there, once. That single layer of tax is the reason many businesses elect S-corporation status. There are narrow exceptions where an S-corporation does owe an entity-level tax, such as built-in gains, but for most the return is informational.
So what does the finished filing produce? Here it is.
One return, and a K-1 for every owner.
Form 1120-S has two outputs that matter. The return itself reports the S-corporation's income and activity to the IRS. Alongside it, each shareholder receives a Schedule K-1 showing their portion of the income, deductions, and credits, which they need to complete their own tax return. Getting the K-1s right and delivered on time is as important as the return, because shareholders cannot finish their personal filings without them. We prepare the return, generate accurate K-1s, e-file, and store everything together.
The S-corporation return has a strict entry requirement. Here is who files it.
Only a valid S-corporation files an 1120-S.
You cannot file Form 1120-S without a valid S-election in place, and the S-corporation itself has eligibility rules. Here is the line.
File Form 1120-S if
- You have a valid S-election, made on Form 2553 and accepted by the IRS.
- The corporation is domestic with no more than one hundred shareholders.
- Shareholders are eligible: generally US individuals and certain trusts and estates.
- The corporation has only one class of stock.
File a different return if
- You have no S-election. That is Form 1120, or make the election first.
- You are a partnership or multi-member LLC without a corporate election. That is Form 1065.
- You are a single-member LLC that is disregarded. Report on the owner's return.
- Your shareholders or stock structure do not meet the S-corporation rules.
A rule specific to S-corporations: an owner who also works in the business is a shareholder-employee and must be paid a reasonable salary through payroll, which is subject to employment taxes, before taking additional profit as a distribution. The IRS scrutinizes S-corporations that pay little or no salary while distributing large profits. We flag this so your 1120-S and your payroll filings line up rather than raising a question.
Election valid? Here are the dates and penalties.
March, not April, and the penalty is per owner.
These figures were verified against current IRS guidance. The per-owner penalty adjusts each year.
Dates in hand? Here is how the filing runs.
From the books to the return and the K-1s.
The return and the shareholder K-1s come from the same records. Here is the sequence.
Confirm the election and ownership
We verify your S-election is valid and capture each shareholder's ownership percentage, which drives the K-1 allocations.
We prepare the return and K-1s
We complete Form 1120-S from your financials and generate a Schedule K-1 for each shareholder with their allocated share.
We e-file and deliver the K-1s
We e-file the return and get each shareholder their K-1 by the deadline, so their personal returns are not held up.
We keep payroll and dates aligned
Next year's deadline goes on your calendar, and we keep the shareholder-employee salary and payroll filings consistent with the return.
The K-1s ripple into personal returns. Here is what we bring to it.
The return, the K-1s, and the payroll it depends on.
An S-corporation return is entangled with its payroll and its owners' personal returns. The value here is a filing where the election, the K-1s, and the reasonable-salary rule all line up, filed by the March deadline.
Election, K-1s, salary aligned
- We confirm the S-election is valid before filing.
- We produce accurate K-1s for every shareholder.
- We flag the reasonable-salary rule so payroll and the return agree.
The March deadline held
- Need more time? We file the 7004 extension first.
- The deadline sits on your compliance calendar.
- The return, K-1s, and payroll filings live together.
Flat preparation fee shown up front. See what it costs →
The S-corp return follows the election and feeds payroll. Here is the road.
The S-corporation runs on a chain of filings.
It starts with the election, files the 1120-S, and depends on payroll for shareholder-employees. They live on one platform, so the chain stays consistent.
Elect it, file it, run payroll, and track it, all inside File.Business. One platform holds the election, the return, and the payroll it depends on.
The questions owners ask about Form 1120-S.
When is Form 1120-S due?
For a calendar-year S-corporation, Form 1120-S is due March 15, which is the 15th day of the third month after the tax year ends. That is a month earlier than the deadline for C-corporations and individuals, and it catches people who assume all business returns are due in April. Filing Form 7004 by March 15 gives an automatic six-month extension to September 15. We confirm your dates based on your fiscal year.
Does the S-corporation itself pay tax?
Generally no. An S-corporation is a pass-through entity, so it usually pays no federal income tax at the entity level. Instead, its income, deductions, and credits flow to shareholders on Schedule K-1, and they pay the tax on their personal returns. There are narrow exceptions where the corporation owes an entity-level tax, most notably the built-in gains tax that can apply to a former C-corporation, but for most S-corporations the return is informational.
What is a Schedule K-1, and when do shareholders need it?
A Schedule K-1 is the statement that reports each shareholder's share of the S-corporation's income, deductions, and credits. Shareholders need it to complete their own tax returns, so the K-1s must go out by the filing deadline. Late or inaccurate K-1s hold up everyone's personal filings, which is why we treat producing them correctly and on time as part of the return itself, not an afterthought.
What is the penalty for filing late?
The S-corporation late-filing penalty is charged per owner, not as a percentage of tax. For a return filed late without a valid extension, it is 255 dollars per shareholder, per month, for up to twelve months, for the 2025 tax year, and the amount is adjusted annually. Because it applies even when no tax is due, a late 1120-S with several shareholders becomes expensive quickly. Filing on time, or extending with Form 7004, avoids it entirely.
Do S-corporation owners have to take a salary?
An owner who works in the business is a shareholder-employee and must be paid reasonable compensation as a salary through payroll, subject to employment taxes, before taking further profit as a distribution. The IRS pays close attention to S-corporations that pay little or no salary while distributing large profits, because it can look like an attempt to avoid employment taxes. We flag this so your payroll and your 1120-S are consistent rather than inviting a question.
What if my S-election is not valid or was never made?
You cannot file Form 1120-S without a valid S-election. If none was made, the corporation is a C-corporation and files Form 1120 instead, unless you make the election in time. If an election was intended but filed late or incorrectly, there are IRS procedures for late-election relief in some circumstances. We confirm the status of your election before filing so the return matches your actual tax classification.
Can Form 1120-S be e-filed?
Yes, and many S-corporations are now required to file electronically. E-filing returns an acknowledgment of receipt, useful as proof of timely filing, and it lets us deliver the K-1s alongside the return efficiently. We e-file wherever available, which is the standard path, and store the acknowledgment and K-1s with your records. Where a specific situation requires a different method, we handle it correctly.