What Expenses Can You Deduct on a House Hack?

In a standard rental, most expenses are obviously rental expenses. In a house hack, a lot of them are mixed — the roof covers your bedroom and the rented one.

That means the useful question isn't "is this deductible," it's "how does this get split."

I am not your CPA. General education about how these categories work, not advice for your situation. What applies to you, and how, is a professional conversation.

The three buckets

Most expenses on a house hack fall into one of three categories.

Directly rental. Costs that exist only because of the rental activity — advertising the room, tenant screening fees, a lock for the rented room, repairs to the rented space specifically. These generally relate entirely to the rental.

Directly personal. Costs relating only to the space you occupy. Generally not deductible as rental expenses.

Shared. Costs covering the whole property — insurance, property taxes, mortgage interest, utilities you cover, roof repairs, HVAC service, landscaping. These typically get allocated between personal and rental use using whatever method you and your CPA establish.

That allocation is the single most important thing to get right early, because it drives most of your tax picture.

Common shared expenses that get allocated

Things that generally cover the whole property and typically get split:

• Mortgage interest
• Property taxes
• Homeowners insurance
• Utilities you're covering
• Internet, if included
• HVAC, roof, plumbing, and other whole-property systems
• Lawn care and exterior maintenance
• Pest control
• HOA dues

Common directly-rental expenses

Things that exist because of the rental activity:

• Listing and advertising costs
• Screening and background check fees
• Lease preparation
• Repairs to the rented space specifically
• Furniture for the rented space, if furnished
• Cleaning between residents
• Rent collection platform fees
• Property management, if you use it

The distinction that trips everyone up

Repairs versus improvements.

Broadly, a repair keeps the property in its current working condition — fixing a leak, replacing a broken window, patching drywall. These are generally treated as current expenses.

An improvement betters the property, restores it substantially, or adapts it to a new use — finishing a basement, adding a bathroom, replacing a roof entirely. These are generally recovered over time rather than deducted immediately.

The line is genuinely blurry in practice, and there are rules and thresholds that affect how it's applied. This is one of the most common areas where people get it wrong, in both directions.

Practical approach: don't try to categorize these yourself from a blog post. Keep the receipt, write a one-line note about what the work actually was, and let your CPA make the call. "Replaced water heater, existing unit failed" is a much more useful note than a receipt with no context.

What you actually need to keep

This is the part that determines whether tax time is easy or awful.

A separate account for the property. Income in, expenses out. Even a separate checking account makes the year enormously cleaner than sorting personal from property transactions in retrospect.

Receipts, categorized as you go. Photograph them. Any expense tracking app works. The method matters much less than the habit.

A written allocation method. How you split shared expenses, the numbers behind it, and when you established it.

A use log. Which spaces were rented, and during what dates. When a room converts from personal to rental use mid-year, that timing matters.

Notes on what work actually was. One line per repair or improvement. Future-you and your CPA will both want this.

The one thing worth spending money on

A CPA who works with rental owners, engaged before you rent anything out.

Not a general-practice accountant who also does taxes — someone who deals with rental property regularly. Ask directly.

The allocation method, how shared spaces are treated, and how to categorize the gray areas are decisions that are cheap to make correctly at the start and expensive to fix later. A single consultation before your first resident moves in is one of the better returns available to a new house hacker.

The framing that helps

Don't think of it as hunting for deductions. Think of it as keeping clean records of what you actually spent, with enough context that a professional can categorize it correctly.

The deductions take care of themselves if the records are good. They're nearly impossible to substantiate if they aren't.