Mixed-Use Expenses: What You Can Deduct (No Guessing)
Mixed-Use Expenses: When an Expense Is Both Business and Personal, What You Can Actually Deduct
If your “business desk” is also where you pay bills, print shipping labels, and scroll TikTok, I get it.
Running a shop or selling online can make life and business feel braided together. And mixed-use expenses are exactly where things get tangled.
The goal is not perfection. It’s knowing what you can deduct, how to back it up, and how to stop guessing with your mixed-use expenses.
What “mixed-use expenses” really means (and why it matters)
Mixed-use expenses are purchases you use for both business and personal life.
Think: your phone, internet, car, laptop, and even that streaming service you use for “shop vibes” and family movie night.
Here’s the simple rule I want you to remember: you can generally deduct the business portion, not the whole thing.
That means your job is to pick a reasonable way to split the expense and keep enough notes to explain it later if you ever need to.
This is where a lot of overwhelmed owners get stuck, because “reasonable” feels squishy.
So I like to treat mixed-use expenses the way I treat inventory counts: don’t eyeball it when you can set a repeatable method.
If this sounds like you…
You have a pile of receipts, but no system
Your bookkeeping categories are a little too “misc”
You tell yourself you’ll “sort it out at tax time”
You are never fully sure what’s deductible
You are not behind because you are lazy. You are behind because you need a simple method that matches real life.
For more info on home office rules: IRS Topic 509: Business use of home.
How to handle mixed-use expenses without guessing
When you’re splitting mixed-use expenses, I want you to pick one of these approaches:
1) Separate it when you can
A separate business phone line, a dedicated business credit card, or a second user profile on your laptop can make this dramatically easier.
2) Allocate by percentage when you can’t
If you only have one phone or one internet bill, choose a business-use percentage you can defend.
A good percentage usually comes from:
a short usage log (even 2–4 weeks helps)
a calendar pattern (workdays vs weekends)
a reasonable estimate you document once, then reuse
3) Keep one layer of backup
Not a binder of doom. Just a quick note:
Phone is ~70% business. Based on calls, admin, vendor orders.
Laptop is ~80% business. Used daily for POS, bookkeeping, email.
If you use bookkeeping software (or even a spreadsheet), that note can live right in the transaction memo.
If this is the part you get stuck on, I break down money systems and routines here: You Can’t Out-Earn Disorganized Finances
Common mixed-use expenses for shops and online sellers
Let’s walk through the big categories I see all the time.
Home office costs
If you have a space you use regularly and exclusively for business, you may be able to deduct a portion of certain home costs.
A practical way many owners think about this is square footage:
workspace square feet ÷ total home square feet = business percentage
Phone and internet
Most shop owners don’t have a “business phone.” They have one phone doing everything.
You can usually deduct the business-use portion, as long as your percentage is reasonable and you keep a quick note on how you got there.
Vehicle use
If you drive for business and personal life, you generally deduct the business portion.
Common business miles include:
trips to the post office for orders
vendor pickups
bank deposits (yes, even if it’s “on the way”)
The IRS publishes standard mileage rates each year if you choose that method.
Travel expenses (business trip + personal time)
This is where people accidentally over-deduct.
A simple rule of thumb: deduct the business portion.
If the primary purpose is business, core travel may be deductible
If you stay extra days for vacation, those extra days are personal
Equipment, software, and subscriptions
If your laptop is 80% business and 20% personal, you generally allocate the cost.
Same with subscriptions:
cloud storage (business files + personal photos)
design tools (marketing + personal projects)
streaming (shop ambiance + home)
If you want help tightening up categories so these don’t live in “misc,” here’s a deeper dive: When To Move From DIY Bookkeeping To Professional Support For Your Shop
Quick wins for mixed-use expenses you can do today
This is the “less thinking, more done” list.
Pick your top 3 mixed-use expenses (usually phone, internet, vehicle) and set one percentage for each.
Create a simple naming rule in your bookkeeping notes: “Phone 70% biz,” “Internet 60% biz,” “Laptop 80% biz.”
Start a mileage log today (app, spreadsheet, or notebook). Consistency beats perfection.
Add a monthly 10-minute review: skim for personal-ish charges that landed in business.
Stop letting subscriptions pile up: if you can’t explain why it exists, cancel or reclassify.
Move mixed-use expenses into clear categories so tax time isn’t a scavenger hunt.
Balanced Path Tip
Make one “Allocation Notes” doc (Google Doc is fine).
List each mixed-use expense, your percentage, and one sentence why.
When tax time comes, you’re not recreating your logic from memory.
If you want a quick set of downloads that supports stronger money habits (without adding more chaos), check out: Balanced Path Resource Library
A simple numbers example: allocating one bill (and keeping it clean)
Let’s make this real with an easy example.
Say your combined phone and internet bill is $200/month.
You estimate (and document) that 70% is business because you use it for:
customer messages
vendor ordering
POS troubleshooting
bookkeeping and website updates
Business portion:
$200 × 70% = $140 deductible business expense
$200 × 30% = $60 personal portion
In bookkeeping, you have a couple clean options:
record the full $200, then adjust $60 as owner draw/personal
split it at entry: $140 to phone/internet expense, $60 to owner draw
The “best” option is the one you will do consistently.
Here’s where records matter most (and what the IRS looks for conceptually): IRS Publication 463
Mixed-Use Expense Deduction Checklist
When it’s time to bring in bookkeeping help
Mixed-use expenses are manageable… until they start stacking up on top of everything else.
It might be time to bring in help if:
You are guessing percentages every year
You are behind on reconciliations, so you can’t trust reports
Your categories are messy, and you can’t find expenses quickly
Tax time feels like a stressful “rebuild the year” project
You want to be confident without obsessing over every receipt
This is also where a bookkeeper can save you money in a boring, practical way: clear categories, consistent allocations, and clean reports that make your tax prep smoother.
If you want to see what ongoing support looks like: Bookkeeping services
And if the real pain is “I just want to file confidently”: Tax services
Key Takeaways
Mixed-use expenses are normal for shop owners and online sellers.
You can generally deduct the business portion, not the whole amount.
A reasonable method + a short note beats last-minute guessing.
The biggest wins come from consistency: same percentages, clean categories, simple reviews.
If you feel stuck, the right support turns this into an easy routine.
Service Links
Visit the Balanced Path Resource Library for downloadable resources.
FAQs
How do I choose a business-use percentage for mixed-use expenses?
Pick a percentage based on something real: a short usage log, your calendar, or a clear work routine. Write one sentence explaining your logic and reuse it consistently.
Can I deduct part of my phone and internet bill?
Often, yes, if you use them for business and you only deduct the business portion. The key is having a reasonable percentage and a quick note on how you calculated it.
What makes a home office deductible?
In many cases, the space needs to be used regularly and exclusively for business. If your “office” is also your guest room or craft corner, it may not qualify the way you hope.
If I add vacation days to a business trip, what can I deduct?
Generally, you deduct the business portion and treat the extra personal days as personal. Keep notes on the business purpose and which days were business activities.
Mileage method or actual expenses: which is better?
It depends on your situation, but whichever method you choose needs consistent records. If you want “easy and consistent,” mileage tracking is often the simplest starting point.
Conclusion
Mixed-use expenses don’t have to feel like a tax-time trap.
When you pick a reasonable percentage, write one quick note, and keep your records consistent, you get cleaner deductions and way less stress.
If you want help sorting your mixed-use expenses, tightening categories, and building a system you can actually keep up with:
Email me at [email protected]
Call/text 603-892-8879
Or book an introduction call here: https://api.leadconnectorhq.com/widget/bookings/bpf-introduction-call
