Self-Employment Tax Calculator for Airbnb Hosts – Schedule C STR Tax Excel

Compute your SE tax. Pay less by knowing the rules. Self-employment tax calculator for Airbnb and STR hosts on Schedule C. Schedule SE-ready, deduction-half built in. Editable Excel.

Most STR income is rental income — Schedule E — and rental income does NOT
trigger self-employment tax. But if you provide substantial services (daily
cleaning, meals, concierge, transportation), the IRS reclassifies you as
running an active business. That triggers Schedule C. And Schedule C income
is subject to a 15.3% self-employment tax on top of regular income tax.

If you're not sure which schedule applies, that's the FIRST tab of this
workbook. If you know you're Schedule C, the rest of the tabs compute your
SE tax cleanly — including the 50% above-the-line deduction most hosts miss.

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WHAT'S INCLUDED
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📋 Schedule E vs C Decision Tab
· The substantial-services test (cleaning during stay, meals, transportation)
· Material-participation thresholds (100+ hours / 750+ hours)
· STR loophole (avg stay ≤ 7 days) interaction
· Routes the workbook accordingly

📋 SE Tax Calculator
· Net SE earnings × 92.35% (the SE adjustment)
· 12.4% Social Security portion (capped at the wage base)
· 2.9% Medicare (uncapped)
· 0.9% Additional Medicare (over $200K single / $250K MFJ)
· Total SE tax — bottom-line dollar amount

📋 50% SE Tax Deduction (above the line)
· Half of your SE tax is an above-the-line deduction
· Reduces your AGI, which reduces income tax
· Most hosts miss this — auto-computed here

📋 Solo 401(k) / SEP IRA Worksheet
· Active-business hosts can shelter up to ~$70K/yr in retirement
· SE tax math feeds the contribution limit calculation
· Decision: Solo 401(k) (employee + employer) vs SEP IRA (employer only)

📋 Quarterly Estimated SE Tax
· Stack with TAX-005 quarterly tax — SE tax flows in
· Avoid underpayment penalty on the SE side

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WHY STR HOSTS NEED THIS
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Two specific traps for active-STR hosts:

1. THE SCHEDULE E vs C ASSUMPTION — most hosts assume Schedule E because
"I rent property." But substantial services flips you to Schedule C.
Getting this wrong either overpays tax (false C filing) or risks
reclassification on audit (false E filing). The decision tab walks
the test cleanly.

2. THE 50% SE TAX DEDUCTION — most active hosts know about SE tax.
Most don't know that half of it is deductible above the line. On
$40K of net SE earnings, that's roughly $2,800 in SE tax × 50% =
$1,400 deduction. At a 24% bracket, $336 in income tax saved that
you wouldn't have caught.

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WHO THIS IS FOR
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· STR hosts on Schedule C (substantial services or active material participation)
· Hosts unsure whether they're Schedule E or Schedule C
· Multi-property operators with co-hosts running active operations
· Anyone whose CPA mentioned "self-employment tax" but didn't show the math

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WHO THIS IS NOT FOR
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· Pure Schedule E hosts who provide only "rental of real estate" services
(no SE tax applies — you don't need this)
· W-2 employees with rental income on the side (Schedule E by default)

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HOW IT WORKS
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1. Open the workbook. Start with the Decision tab.
2. Answer the substantial-services + material-participation questions.
3. The workbook routes you to Schedule E (no SE tax) or Schedule C (SE tax applies).
4. If C: enter your net SE earnings on the SE Calculator tab.
5. The 50% SE-tax deduction auto-computes. The total SE owed appears on the Summary.
6. Optionally walk the retirement worksheet to shelter contributions.

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FILE COMPATIBILITY
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✅ Microsoft Excel 2016+ (Windows and Mac)
✅ Microsoft Excel 365
✅ Google Sheets

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REFUNDS + SUPPORT
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14-day refund, no questions asked. Email hello [!at] thestrledger.com — real humans,
fast replies.

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ABOUT THE STR LEDGER
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Business-grade Excel systems for serious short-term rental hosts.
Full template library at thestrledger.com.

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⚠ Digital product. Not tax advice. Consult your CPA. IRS Schedule SE instructions and
Pub 334 (Tax Guide for Small Business) are the canonical references.