Tax Strategies for Inland Empire Contractors: A CPA's Guide

The Inland Empire is one of the most active construction and trades markets in Southern California. Between commercial development in Ontario and Fontana, residential growth pushing east from the 15, and the ongoing demand for home improvement and renovation work throughout the region, contractors here have plenty of opportunity — and plenty of complexity when it comes to their taxes.

Whether you're a general contractor, electrician, plumber, HVAC tech, or specialty subcontractor, your tax situation has some specific wrinkles that a general accountant without trades experience may not catch. This guide covers the areas where we most commonly see Inland Empire contractors overpay or get into compliance trouble.

Vehicle and Equipment: Your Biggest Deductions

For most contractors, vehicles and equipment represent the largest pool of available deductions — and also the area with the most specific rules.

Vehicle Deductions

You have two options for deducting vehicle costs: the standard mileage rate or actual expenses. The right choice depends on your specific situation, and it can't be changed retroactively once you've started.

• Standard mileage rate: For 2025, the IRS rate is 70 cents per mile for business use. Simple to track, but you must log every business trip.
• Actual expense method: Deduct a percentage of gas, insurance, repairs, registration, and depreciation based on the percentage of miles driven for business. Often more valuable for contractors driving heavy-use work trucks.

The critical rule: commuting from home to your first job site is not deductible. But if you have a legitimate home office or storage yard (more on this below), your first drive of the day may qualify as business travel. This distinction alone is worth thousands of dollars per year for contractors who are unaware of it.

Section 179 and Bonus Depreciation

Section 179 allows you to deduct the full cost of qualifying equipment in the year it's purchased, rather than depreciating it over multiple years. For contractors, this includes tools, machinery, trailers, and certain vehicles — potentially writing off a significant purchase immediately rather than over five to seven years.

The 2025 Section 179 deduction limit is $1,220,000. Bonus depreciation (which was 100% through 2022) has been phasing down — it's currently at 40% for 2025 equipment placed in service. The interplay between Section 179 and bonus depreciation can get complicated, but the takeaway is: major equipment purchases in a high-income year can dramatically reduce your tax bill if planned correctly.

Home Office and Storage Deductions

Many contractors run their administrative operations out of a home office — scheduling, invoicing, estimating, vendor calls. If you use a portion of your home regularly and exclusively for business, that space is deductible. This applies whether you own or rent.

The deduction is calculated by the percentage of your home's square footage dedicated to business use. On a 2,000 sq. ft. home with a 200 sq. ft. office, that's 10% of your mortgage interest, property taxes, utilities, insurance, and depreciation — or a simplified method of $5 per square foot up to 300 sq. ft.

Additionally, if you store tools, equipment, materials, or job supplies at home — in a garage, shed, or yard — that storage area may also qualify for a deduction. The exclusive-use test applies differently here: storage space doesn't need to be used solely for business, as long as it's used regularly for inventory or equipment storage.

Subcontractors: 1099s, AB5, and Your Liability

If you hire subcontractors, you're navigating one of the most scrutinized areas of California employment law. California's AB5 significantly tightened the rules for classifying workers as independent contractors, and the construction industry is not exempt from it.

Under AB5's ABC test, a worker is presumed to be an employee unless you can show all three of the following:

• The worker is free from your control and direction in performing the work
• The worker performs work that is outside the usual course of your business
• The worker is customarily engaged in an independently established trade or occupation

For general contractors, the second prong is often the problem — a framing sub working on a framing job for a framing contractor looks a lot like an employee under California's interpretation. The CSLB has its own licensing requirements for subcontractors that interact with this as well: an unlicensed sub performing work over $500 creates additional liability for the GC.

On the federal side, you're required to issue a 1099-NEC to any unincorporated subcontractor you paid $600 or more during the year. Failure to file results in penalties, and the IRS is increasingly matching 1099 data with contractor returns.

Quarterly Estimated Taxes: Don't Get Caught Short

Project-based income is inherently irregular, but tax payments aren't. Self-employed contractors are required to pay estimated taxes four times per year — and California requires its own set of estimated payments on top of federal.

California's estimated payment schedule is front-loaded in a way that catches a lot of people off guard. The first installment covers 30% of your estimated annual tax, the second covers 40%, and the final two cover 0% and 30% respectively. If you're making irregular payments throughout the year, you may be underpaying on the front end even if you catch up later — which still triggers an underpayment penalty.

A practical approach for contractors with variable income: set aside 25–30% of every payment you receive into a separate savings account, then make your quarterly payments from that reserve. It's simple and prevents the scramble at the end of the year.

Licensing, Bonding, and Continuing Education

CSLB license fees, bond premiums, continuing education costs, and union dues are all fully deductible business expenses that contractors sometimes overlook or misclassify. These aren't large numbers individually, but they add up — and they're yours to take.

The same applies to professional liability (E&O) insurance, general liability premiums, and workers' comp premiums paid for employees. These are above-the-line business deductions that reduce your gross income before you even get to itemized deductions.

Entity Structure: When to Consider an S-Corp

Most contractors in the Inland Empire start as sole proprietors or single-member LLCs. That works, but as your net profit grows, it becomes increasingly expensive from a self-employment tax standpoint — 15.3% on net self-employment income up to the Social Security wage base, plus 2.9% on anything above that.

An S-corporation election allows you to split your business income between a reasonable salary (subject to payroll taxes) and a distribution (not subject to self-employment tax). For a contractor netting $120,000 to $150,000 per year, this can represent $8,000 to $15,000 in annual tax savings — well above the cost of administering payroll and filing an S-corp return.

The math doesn't work the same way for everyone. The break-even point depends on your income level, what constitutes a "reasonable salary" in your trade, and California's additional franchise tax and payroll obligations. But if you've never had this conversation with a CPA, it's worth having.

Year-End Planning: Don't Wait Until April

The best time to take action on any of the above is before December 31. Equipment purchases, retirement contributions, entity elections — many of the most impactful tax decisions have year-end deadlines. A quick check-in with your accountant in October or November gives you time to act. A call in March gives you very few options.

We work with contractors throughout Rancho Cucamonga and the broader Inland Empire — from sole operators to established firms with crews and multiple vehicles. If you want a straightforward look at whether your current setup is costing you more than it should, let's talk.