Business Tax Preparation

(S-Corp, C-Corp, Partnership/LLC)

Accurate, compliant returns—built on clean books and clear communication.

Business tax returns are too important to leave to chance (or generic software).

Cornerstone CPA prepares business tax returns for S-Corporations, C-Corporations, and Partnerships/LLCs. We focus on clean, accurate filings that reflect your books, minimize surprises, and make next year’s planning easier.

Who This Is For

S-Corp, C-Corp, and Partnership/LLC owners
Businesses that want a licensed-prepared return and ongoing relationship—not just a one-off filing
Existing bookkeeping clients who want tax and books under one roof

What's Included

1. Preparation and filing of your federal business income tax return:
- 1120-S (S-Corporation)
- 1120 (C-Corporation)
- 1065 (Partnership/LLC)
2. K-1 preparation for owners/partners
3. Required supporting schedules (e.g., depreciation, basis, etc.)
4. Additional state business returns, if applicable
5. Final return review and e-file confirmation
6. Email support for questions related to the filed return

How it Works

15-Minute Discovery Call (Free)

Quick call to learn about your business and see if we’re a good fit.

Document
Upload

You provide:
- Prior-year 990 (if available)
- Year-end financial statements
- Board list and other required details

Preparation & Review

We prepare the draft 990 and walk through it with you—especially the public-facing sections—to make sure it aligns with your story.

Filing &
Follow-Up

We e-file, provide confirmation, and send board-ready copies as needed.

PRICING

Starting at:

1. 1120-S (S-Corporation): from $1,400
2. 1120 (C-Corporation): from $1,400
3. 1065 (Partnership/LLC): from $1,500

Additional state business returns: generally from $150 per state