Business Accountant Long Island | Tax Accountant Nassau & Suffolk | OnPoint
Business Accountant on Long Island
Tax preparation, bookkeeping, and accounting for Long Island small businesses, LLCs, S-Corps, and professional practices. Serving Nassau and Suffolk counties.
Long Island Business Tax & Accounting Services
OnPoint Business Tax & Accounting serves Long Island business owners across Nassau and Suffolk counties — from Garden City, Hempstead, and Great Neck to Huntington, Babylon, and Patchogue. Our enrolled agents and tax professionals work exclusively with small and mid-size businesses, delivering expert tax and accounting services at a transparent flat fee.
Long Island businesses face a unique mix of NYS, Nassau, and Suffolk tax obligations. We handle your federal and state returns, monthly bookkeeping, sales tax filings, and year-round tax planning — so you can focus on running your business instead of chasing paperwork.
What's Included
A complete Long Island accounting and tax service — not just a transaction.
Business Tax Preparation
Federal and NY State returns for LLCs, S-Corps, C-Corps, partnerships, and sole proprietors — filed accurately and on time.
Bookkeeping & QuickBooks
Monthly bookkeeping, bank reconciliations, and QuickBooks setup and cleanup so your financials are always current.
Tax Planning
Year-round strategy to reduce your tax liability — S-Corp elections, retirement contributions, depreciation, and more.
NYS & Local Compliance
NYS income tax, sales tax filings, and payroll tax compliance handled by professionals who know New York State requirements.
Unfiled & Back Taxes
Behind on multiple years? We prepare and file all outstanding returns and help you resolve IRS and NYS balances.
New Business Formation
LLC and corporation formation, EIN registration, and first-year tax setup for new Long Island businesses.
Flat-Fee Pricing — No Surprises
You know exactly what you'll pay before we start. No hourly billing, no hidden charges.
100% In-House — Never Outsourced
Every return, every filing, every call is handled by our own licensed team.
Everything We Handle for You
OnPoint delivers a complete, end-to-end Long Island accounting and tax service — no hand-offs, no surprises.
- Business tax returns — LLC, S-Corp, C-Corp, partnership
- Monthly bookkeeping and bank reconciliations
- QuickBooks setup, cleanup, and training
- NYS income and sales tax filings
- Payroll tax compliance and filings
- Unfiled and back-year tax returns
- IRS and NYS tax resolution
- New business formation and EIN setup
- Tax planning and S-Corp elections
Why OnPoint?
Long Island's Trusted Business Tax Experts
- Circle of Excellence 2025 Award Recipient
- 5-star rated on Google Reviews
- Serving NYC & NJ businesses for over a decade
- Flat-fee pricing — you know the cost upfront, always
- 100% in-house — your work is never outsourced or offshored
- Bilingual staff — English & Spanish
- In-person, virtual, and drop-off options
Work with a Long Island Business Accountant
We serve Long Island businesses remotely and in-person at our Manhattan office. Call us or request a free quote today.
NYC Office — 100 Church Street, New York, NY 10007
Serving Long Island businesses remotely and in-person. Mon–Fri 9 AM–6 PM & Sunday 10 AM–4 PM.