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NorthlineAdvisory

Services

Corporate Tax

Federal, state and city corporate tax planning and filing for C-corps, S-corps and partnerships.

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Starting at $3,500/yr

Overview

Corporate tax in New York means juggling federal, New York State and New York City rules, each with its own deadlines, apportionment formulas and credits. One missed election or estimated payment can cost far more than our annual fee.

Our corporate tax team prepares and files your returns, and plans year-round so there are no surprises in March. We model entity choices, R&D credits, Section 179 and bonus depreciation, and multi-state nexus before decisions are made, not after.

What's included

  • Federal Form 1120, 1120-S or 1065 preparation and e-filing
  • New York State CT-3 / CT-3-S and NYC corporate returns
  • Quarterly estimated tax calculations and payment reminders
  • R&D tax credit studies and payroll tax offset for startups
  • Multi-state nexus review and apportionment
  • Year-end tax planning meeting with a senior CPA
  • IRS and state notice response included

How it works

  1. Step 1

    Discovery

    We review prior returns, entity structure and current-year results to spot risks and savings.

  2. Step 2

    Planning

    You get a written tax plan with estimated liabilities, elections and action items by quarter.

  3. Step 3

    Preparation

    We prepare every return, with a second CPA reviewing each filing before you sign.

  4. Step 4

    Filing & support

    We e-file, confirm acceptance and handle any notices that follow at no extra charge.

Frequently asked questions

When is the corporate tax deadline for calendar-year companies?

S-corps and partnerships file by March 15 and C-corps by April 15. Extensions give you six more months to file, but not to pay, so we calculate and remit any balance due by the original deadline.

Do you handle New York City corporate tax?

Yes. We prepare NYC Business Corporation Tax and General Corporation Tax returns, and Unincorporated Business Tax for LLCs and partnerships operating in the five boroughs.

Can you take over mid-year from another accountant?

Absolutely. Most new clients switch mid-year. We request workpapers from your previous firm and complete a transition review within two weeks.

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