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Home/Services/Tax Preparation/S-Corp 1120-S
Form 1120-S · S Corporation · K-1 schedules · Basis tracking · White-label · Reviewer-ready

Offshore S-Corp (1120-S) Tax Return Preparation for CPA Firms.

S-Corp returns carry complexity that makes them time-consuming to prepare correctly. shareholder allocations, K-1 schedules, AAA account tracking, basis calculations, reasonable compensation considerations — every one of these requires careful handling before a return is reviewer-ready. our certified offshore accountants manage the preparation from source documents to completed 1120-S. your CPAs review, apply judgment, and sign. nothing more.

Book a discovery call All business returns →
Turnaround at a glance
Standard48–72 hrs
Peak season72–96 hrs
K-1 allocation checkEvery return
AAA trackingStandard
SoftwareYours
Scope of work

What we handle on every 1120-S.

Every item below is covered as standard on each S-Corp return we prepare. K-1 accuracy and AAA tracking are built into the process — not optional add-ons.

Quality checkpoint
K-1 allocations verified against the operating agreement before K-1s are generated.
Full Form 1120-S preparation from trial balance and source documents
Income and loss allocation across all shareholders
Schedule K-1 preparation for each shareholder
Accumulated Adjustments Account (AAA) and Other Adjustments Account (OAA) tracking
Built-in gains tax calculations for S corporations with prior C-Corp history
Shareholder basis schedule preparation and maintenance
State S-Corp returns in all applicable states
Reasonable compensation documentation support
Estimated tax payment schedule for shareholders
Software we work in

Your software. your environment. no migration required.

We work inside your existing software setup. you add us as a user, we prepare in your environment, the file stays in your system.

Drake Tax
Lacerte
ProConnect Tax Online
CCH Axcess
ProSeries
UltraTax CS
How a return moves through the workflow
1
Your client sends source documents to your firm
2
You securely share documents with your offshore team
3
We prepare the 1120-S and all K-1 schedules in your software
4
Internal QA reviews before returning to you
5
Youreview, approve, and sign under your firm's name
Our preparation process

Four stages. clean handoff at every step.

A documented, repeatable process for every 1120-S — so your review starts where it should.

Step one
Prior year review and intake
We review the prior year 1120-S, note the shareholder composition, confirm AAA and basis carry-forward positions, and identify any elections in effect. source documents received and reviewed for completeness before preparation begins.
Step two
Preparation
Full 1120-S and all K-1 schedules prepared in your software. shareholder allocations verified against the operating or shareholder agreement before K-1s are generated — allocation errors are among the most consequential S-Corp preparation mistakes and we catch them at the source.
Step three
Internal QA
Senior accountant review before delivery. all schedules verified, K-1 totals reconciled to the return, state returns cross-checked. items requiring your professional judgment flagged in preparer notes.
Step four
Delivery
Reviewer-ready file delivered in your software with all supporting schedules complete.
Turnaround times

Confirmed timelines. volume commitments agreed at engagement start.

Standard48–72 hours from receipt of complete source documents
Peak season72–96 hours — volume commitments agreed at engagement start
Quality control

K-1 allocation accuracy is the most critical checkpoint.

before any K-1 is finalized, our accountants verify allocations against the governing agreement. a senior accountant reviews all schedules and the reconciliation between individual K-1s and the return totals before delivery.

You receive returns where the preparation has been verified. your review is the professional sign-off — not error detection.

1
Allocations verified against governing agreement
2
K-1 totals reconciled to the return
3
Senior accountant full schedule review
4
Your review — the professional sign-off
Related entity tax preparation

Other business entity returns we prepare.

1120.
C Corporation Tax Return
Income reconciliation, M-1/M-3 book-to-tax adjustments, NOL carryforwards, multi-state apportionment, and consolidated returns.
View C-Corp preparation →
1065.
Partnership & LLC Tax Return
Partner K-1 schedules, capital account maintenance, outside basis tracking, and multi-member LLC filing.
View Partnership preparation →
1041.
Estate & Trust Tax Return
Fiduciary returns with distributable net income calculations, beneficiary K-1 preparation, and passive activity tracking.
View Estate & Trust preparation →

Related entity returns

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