What Is the Useful Life for Depreciation of a Semi-Truck?

For federal tax purposes, a semi-truck is depreciated over 5 years under the IRS’s MACRS depreciation system.

1. IRS-Defined Useful Life (MACRS)

The IRS assigns assets to “recovery periods” rather than letting taxpayers choose their own useful lives.

• Semi-truck tractor units used over the road are classified as 3-year property (4 years under ADS), and truck trailers as 5-year property (6 years under ADS)
• Depreciation is generally calculated using:
  
  • MACRS
  • 200% declining balance, switching to straight-line when beneficial

2. When the 5-Year Clock Starts

Depreciation begins when the semi-truck is:

• Placed in service, meaning
• It is ready and available for business use

This is often not the purchase date if the truck required setup, registration, or modification first.

3. Common Depreciation Methods for Semi-Trucks

A. Standard MACRS (Most Common)

• 5-year recovery period
• Accelerated depreciation in early years

B. Section 179 Expensing (If Eligible)

You may be able to expense part or all of the cost upfront instead of depreciating over 5 years.

Key points (2025 rules, subject to annual limits):

• Must be used more than 50% for business
• Deduction limited to taxable business income

C. Bonus Depreciation

Under the One Big Beautiful Bill Act, trucks and trailers acquired and placed in service after January 19, 2025 qualify for a permanent 100% bonus depreciation deduction

For property acquired before January 20, 2025 and placed in service in 2025:

• Bonus depreciation is 40%

Bonus depreciation applies before regular MACRS.

4. What If the Semi-Truck Is Used Personally Too?

If the semi-truck is:

• Used partly for business and partly for personal use

Then:

• Depreciation must be prorated
• Section 179 and bonus depreciation may be limited or disallowed

5. Sale or Trade-In Before 5 Years

If you sell or trade the semi-truck before fully depreciating it:

• Depreciation stops
• You may have:
  
  • Depreciation recapture (taxed as ordinary income)
  • Capital gain or loss

6. Common Misconceptions

• “A semi-truck is depreciated over 7 or 10 years” → Incorrect
• “Useful life depends on mileage” → Incorrect for tax
• “Older used trucks have a different life” → Incorrect

The IRS recovery period is fixed by asset class (3 years for tractors, 5 years for trailers), regardless of age or miles.

Summary

• A semi-truck tractor has a 3-year depreciation life (trailers 5 years) for federal tax purposes
• Depreciated under MACRS
• May qualify for Section 179 and bonus depreciation
• Depreciation starts when the truck is placed in service
• Sale before full depreciation may trigger recapture tax

Related Questions

• What is qualified improvement property QIP?
• What Is the Depreciation Schedule for Computers Used for Business?
• What was federal bonus depreciation in 2025?

Source:

IRC §168(e)(3)(B)(i)

IRS Publication 946, How To Depreciate Property

IRC §179

IRC §168(k)

IRS Publication 334, Tax Guide for Small Business

IRC §1245

IRS Publication 544, Sales and Other Dispositions of Assets