BUSINESS TAX

Business Tax Returns

Every entity type. Every deduction. Filed correctly.

From sole proprietor Schedule C returns to multi-entity S-Corp and partnership filings — we handle your business taxes accurately, completely, and on time.

Virtual across Washington State. In person at our Bothell office.

Call +1 (425) 699-6990

WHAT WE FILE

Every Business Structure

From a sole proprietor Schedule C to multi-entity S-Corps and partnerships — we prepare business tax returns for every structure.

Sole Proprietor (Schedule C)

Reported on your individual return. Due April 15 for calendar-year filers.

Single & Multi-Member LLC (Schedule C or Form 1065)

A single-member LLC is reported on Schedule C unless it elects corporate treatment. A multi-member LLC files Form 1065, due March 15 for calendar-year filers.

S-Corporation (Form 1120-S)

Due March 15 for calendar-year filers, with a K-1 for each shareholder. Form 7004 extends the filing deadline six months.

Partnership (Form 1065)

Due March 15 for calendar-year filers, with a K-1 for each partner.

C-Corporation (Form 1120)

Due April 15 for calendar-year corporations. Form 7004 extends the filing deadline six months.

Estates, Trusts & Non-Profits

Form 1041 is due April 15 for calendar-year estates and trusts. Form 990 is due on the 15th day of the fifth month after year end — May 15 for calendar-year organizations.

Multi-State Business

Nexus review and additional state returns when you do business beyond Washington.

WHAT WE LOOK FOR

Deductions & Credits We Find

The Qualified Business Income deduction — made permanent in 2025 — can reduce taxable income by up to 20% for eligible pass-through businesses, and it is one of the most commonly missed deductions on self-prepared returns.

Deductions

Qualified Business Income (QBI)
Section 179 Expensing
Bonus Depreciation
Home Office Deduction
Vehicle & Mileage
Business Meals & Travel
Employee Wages & Benefits
Professional Services
Equipment & Technology
Marketing & Advertising

Tax Credits

R&D Tax Credit
Small Business Health Care
Retirement Plan Startup Credit
Auto-Enrollment Credit
Disabled Access Credit
Family & Medical Leave Credit

COMPLEX SITUATIONS

Business Situations We Handle

Most business tax issues come from entity structure, owner compensation, and Washington state obligations that generalist preparers miss.

First Year Business Filing
Switching Accountants Mid-Year
S-Corp Election Timing
Prior Year Return Review
Owner Salary vs Distribution
Multi-Entity Structures
Reasonable Compensation Analysis
Business Sale or Closure
Quarterly Estimated Payments
Washington B&O Tax
Retirement Plan Setup
Contractor vs Employee
Home-Based Business
Startup Cost Deductions

WASHINGTON

Washington Business Taxes

Washington has no state income tax on business profit, but it does have the Business and Occupation (B&O) tax — a tax on gross receipts, not profit. (A new 9.9% tax on household income above $1 million takes effect in 2028 and faces legal challenges, but it won't affect most households.) Retailing is taxed at 0.471% and wholesaling at 0.484%. Since October 1, 2025, the Service and Other Activities classification has three rates based on prior-year income: 1.5% under $1 million, 1.75% from $1 million to under $5 million, and 2.1% at $5 million or more. There are no deductions for wages, materials, or rent.

You must register with the Department of Revenue if your gross income is $12,000 or more a year, or if you collect sales tax. Once registered, you file on the schedule the Department assigns. If tax is paid late, the Department adds a 9% penalty, rising to 19% and then 29% the longer it stays unpaid. Several cities, including Seattle, Bellevue, and Tacoma, also levy their own B&O tax.

Industry rules change the picture. Contractors report most construction under Retailing, and gas stations report fuel, groceries, lottery commissions, and ATM income in different ways — see our pages for general contractors and gas station owners.

We prepare business returns for owners across the state, in person through our Bothell tax preparation office and virtually for clients in Bellevue and beyond. If you are weighing an S-Corp election, start with our guides on LLC vs S-Corp tax differences and reasonable compensation.

COMMON MISTAKES

Errors We Fix Most Often

These are the problems we see most often on business returns prepared elsewhere.

S-Corp Owner Taking No Salary

An S-Corp owner who works in the business must be paid reasonable compensation through payroll before taking distributions.

Missing the QBI Deduction

Eligible pass-through owners can deduct up to 20% of qualified business income. For 2026, limits phase in above $201,750 of taxable income ($403,500 for joint filers).

Not Issuing 1099-NECs

For payments made in 2026, you must issue Form 1099-NEC to non-employees you paid $2,000 or more for services. The forms are due January 31.

Mixing Personal and Business Spending

Commingled accounts make deductions harder to support and books harder to close. Business spending belongs in a business account.

Filing B&O on Profit Instead of Gross Receipts

Washington B&O tax is calculated on gross receipts. Reporting net income understates the tax and invites an assessment.

No K-1 Basis Tracking

Partners and shareholders can only deduct losses up to their basis. Without a basis schedule, losses and distributions are easy to get wrong.

WHAT TO HAVE READY

Documents to Bring

Business returns are priced on reconciled books. If your books are behind, see our catch-up bookkeeping service first.

Prior-year business return
Year-end profit & loss statement
Year-end balance sheet
Bank and credit card statements
Payroll reports (941s, W-2s, W-3)
1099s you issued and received
Invoices for equipment bought or sold
Loan statements
Vehicle mileage logs
Owner contributions and distributions
Washington B&O returns filed
Entity documents and EIN letter

PRICING

What It Costs

Transparent flat rates for every entity type. Final pricing depends on your business's complexity — we'll always confirm your quote before we begin.

See full business pricing →

S-Corporation (Form 1120-S)Starting at $1,350

Partnership (Form 1065)Starting at $1,350

C-Corporation (Form 1120)Starting at $1,650

Estate & Trust (Form 1041)Starting at $1,250

Non-Profit (Form 990)Starting at $950

WA B&O Excise Tax Filing$250

Additional State Corporate Return$250 per state

Additional Schedule K-1 (3rd onward)$150 each

New Customer Discount−$250 first year

S-Corporation and partnership prices include up to 2 K-1s and your home state return, and require reconciled books.

How It Works

Free consultation to understand your business structure and filing needs

We send you a customized document checklist specific to your entity type

We prepare your complete return and review every line together before filing

We e-file and provide you a copy for your records

Common Questions

For calendar-year businesses: partnerships (Form 1065) and S-Corporations (Form 1120-S) are due March 15, C-Corporations (Form 1120) and estates and trusts (Form 1041) are due April 15, and sole proprietors file Schedule C with their individual return by April 15. Form 7004 extends the filing deadline — not the payment deadline.

For payments made in 2026 and later, you must issue Form 1099-NEC to non-employees you paid $2,000 or more for services in the course of your business. The threshold was $600 for payments made through 2025. Forms are due to the contractor and the IRS by January 31.

It lets eligible owners of pass-through businesses — sole proprietorships, partnerships, S-Corps, and many LLCs — deduct up to 20% of qualified business income. It was made permanent in 2025. For 2026, wage and property limits and service-business restrictions phase in above $201,750 of taxable income, or $403,500 for joint filers.

B&O tax is charged on gross receipts, with no deduction for costs. The rate depends on your classification: 0.471% for retailing, 0.484% for wholesaling, and 1.5%, 1.75%, or 2.1% for service and other activities depending on prior-year income. You must register if your gross income is $12,000 or more a year.

Enough to be reasonable for the services you perform — generally what the business would pay someone else to do your job. We document a defensible figure as part of every S-Corp return and payroll setup.

S-Corporation and partnership returns start at $1,350, C-Corporations at $1,650, estates and trusts at $1,250, and non-profits at $950. New business clients receive a $250 first-year credit. See business tax pricing.

RELATED SERVICES

GET STARTED

Ready to File Your Business Return?

Starting at $1,350 for S-Corps and partnerships. Quote confirmed before we start. Virtual across Washington State or in person in Bothell.