7 Mistakes New Architecture Firms Make in Their First Year

2026-08-21

Avoid common tax pitfalls in your first year as an architecture firm. Learn the 7 mistakes and practical steps to save money and stay compliant.

Starting an architecture firm is exciting, but the first year is also when many owners make costly tax mistakes. From misclassifying workers to missing deductions, these errors can lead to penalties and missed savings. Here are the 7 most common tax mistakes new architecture firms make, and how to avoid them.

1. Choosing the Wrong Business Structure

Many new architects default to a sole proprietorship or a simple LLC without considering the tax implications. As a sole proprietor, you pay self-employment tax on all net income, which is 15.3% in 2026. An S-corp can save you money on self-employment tax by paying yourself a reasonable salary and taking the rest as distributions, which are not subject to self-employment tax. However, S-corps require more paperwork and payroll. For a firm with net income above $40,000, the savings often outweigh the hassle. Consult a CPA to determine the best structure for your situation.

2. Not Tracking Expenses from Day One

In the first year, it’s easy to mix personal and business expenses, especially if you use a personal credit card. This creates a mess at tax time and you may miss deductions. Set up a separate business bank account and credit card immediately. Use accounting software like QuickBooks or Xero to categorize expenses weekly. Common deductible expenses for architecture firms include:

Software subscriptions (CAD, BIM, rendering)
Professional liability insurance
Office rent and utilities
Marketing and website costs
Continuing education courses
Travel for client meetings

3. Misclassifying Employees as Independent Contractors

Many new firms hire freelancers to save on payroll taxes, but the IRS has strict rules. If you control how, when, and where the work is done, the worker is likely an employee. Misclassification can result in back taxes, penalties, and interest. For example, if you hire a part-time drafter to work in your office 20 hours a week, they are probably an employee. If you hire a structural engineer who has their own business and works for multiple clients, they are likely an independent contractor. When in doubt, file Form SS-8 with the IRS to get a determination.

4. Ignoring Quarterly Estimated Taxes

As a business owner, you are responsible for paying taxes throughout the year. If you expect to owe more than $1,000 in taxes, you must make quarterly estimated payments. New architects often miss these deadlines, leading to underpayment penalties. For 2026, the due dates are April 15, June 15, September 15, and January 15. Calculate your estimated payments based on your projected income and expenses. Use IRS Form 1040-ES or have your accountant help. Set reminders and pay on time.

5. Overlooking Home Office Deduction

If you run your firm from home, you can deduct a portion of your rent, utilities, and internet. The simplified method allows $5 per square foot, up to 300 square feet, for a maximum deduction of $1,500. The regular method requires calculating actual expenses based on the percentage of your home used for business. Many architects overlook this deduction because they fear an audit, but it’s legitimate if you meet the requirements: the space must be used regularly and exclusively for business. Keep a log of your business use.

6. Failing to Take Advantage of the QBI Deduction

The Qualified Business Income (QBI) deduction allows you to deduct up to 20% of your qualified business income from your taxes. This applies to sole proprietors, LLCs, and S-corps. For 2026, the deduction is subject to income thresholds: for single filers, the threshold is $182,100; for married filing jointly, it’s $364,200. Above these thresholds, the deduction may be limited based on W-2 wages and property. Many new architects don’t realize they qualify, so they miss out on significant savings. Work with your accountant to ensure you claim this deduction correctly.

7. Not Planning for Tax Deadlines and Payments

Finally, many new firms fail to set aside money for taxes. When the tax bill comes due, they scramble to find cash. A good rule of thumb is to set aside 25% to 30% of your net income for taxes. Open a separate savings account and transfer this amount each month. Also, mark your calendar for all tax deadlines, including filing extensions. If you can’t pay in full, the IRS offers payment plans, but interest and penalties will accrue.

FAQ

What is the best business structure for a new architecture firm?

For most new firms, an LLC is a good starting point because it offers liability protection and flexibility. However, if you expect to earn more than $40,000 in net income, consider an S-corp to save on self-employment taxes. Consult a CPA to make the right choice.

How much should I set aside for taxes?

Aim to set aside 25% to 30% of your net income. This covers federal income tax, self-employment tax, and state taxes. If you have employees, you’ll also need to withhold payroll taxes.

Can I deduct software subscriptions like AutoCAD?

Yes, software subscriptions are deductible as business expenses. This includes CAD, BIM, rendering, and project management tools. Keep receipts and log the business use.

What if I miss a quarterly estimated tax payment?

If you miss a payment, pay it as soon as possible to minimize penalties. The IRS charges interest on underpaid estimated taxes. You can also adjust your withholding if you have a W-2 job, but as a business owner, you’ll need to stay on top of quarterly deadlines.

The bottom line

Your first year as an architecture firm is a learning curve, but tax mistakes can be avoided with planning. Choose the right business structure, track expenses, classify workers correctly, and pay estimated taxes on time. Take advantage of deductions like home office and QBI. Set aside money for taxes and consult a professional. By avoiding these 7 mistakes, you’ll keep more of your hard-earned revenue and stay on the right side of the IRS.