Updated October 18, 2026. Quick answer: Line 20a is for rent or lease cost of vehicles, machinery and equipment, and line 20b is for other business property such as office space. Line 21 is for incidental repairs and maintenance. Line 22 is for supplies you consumed in the business and did not already count in Part III.
Picking the Schedule C business code for your work (2025 chart): Schedule C code for handymen and Schedule C code for construction trades.
Picking the Schedule C business code for your work (2025 chart): Schedule C code for photographers, Schedule C code for house cleaners and Schedule C code for hair, nail, and beauty.
S corporation return (Form 1120-S) for 2025, read line by line: Form 1120-S lines 7 to 12.
Partnership return (Form 1065) for 2025, read line by line: Form 1065 lines 11 to 14.
Business use of your home (Form 8829), the saver’s credit (Form 8880), clean vehicle credits (Form 8936) and amended returns (Form 1040-X), read line by line: Form 8829 lines 1 to 7 and Form 8829 lines 16 to 27.
Lines 20a and 20b: rent or lease
The form’s captions read “Rent or lease (see instructions)”, with “Vehicles, machinery, and equipment” on line 20a and “Other business property” on line 20b. The instructions say “If you rented or leased vehicles, machinery, or equipment, enter on line 20a the business portion of your rental cost.” “Enter on line 20b amounts paid to rent or lease other property, such as office space in a building.”
For a leased vehicle: “if you leased a vehicle for a term of 30 days or more, you may have to reduce your deduction by the inclusion amount.” “See Leasing a Car in chapter 4 of Pub. 463 to figure this amount.”
Line 21: repairs and maintenance
The caption reads “Repairs and maintenance”. The instructions say “Deduct the cost of incidental repairs and maintenance that do not add to the property’s value or appreciably prolong its life.” “Do not deduct the value of your own labor.” “Do not deduct amounts spent to restore or replace property; they must be capitalized.” Capitalized costs are typically recovered through depreciation, which is covered on the Form 4562 page.
Line 22: supplies
The caption reads “Supplies (not included in Part III)”. Costs counted in Part III are covered on the Schedule C Part III page. For line 22 the instructions say “In most cases, you can deduct the cost of materials and supplies only to the extent you actually consumed and used them”; the sentence continues onto the next page of the instructions, so read it in full there.
For incidental supplies: “if you had incidental materials and supplies on hand for which you kept no inventories or records of use, you can deduct the cost of those you actually purchased during the tax year, provided that method clearly reflects income.”
For books and equipment: you “can also deduct the cost of books, professional instruments, equipment, etc., if you normally use them within a year.” “However, if their usefulness extends substantially beyond a year, you must generally recover their costs through depreciation.”
Where the number comes from
Line 20a comes from the business portion of what you paid to rent or lease vehicles, machinery or equipment, and line 20b comes from amounts paid to rent or lease other property. Line 21 comes from repair invoices. Line 22 comes from supply receipts, adjusted for what you actually used. If you produced real or tangible personal property or acquired real or personal property for resale, the instructions say to “Reduce the amounts on lines 8 through 27a and Part V by amounts capitalized.”
Where it goes next
Each Part II expense line is a step toward the total on line 28. The form describes it as “Total expenses before expenses for business use of home. Add lines 8 through 27b”. Line 29 then reads “Tentative profit or (loss). Subtract line 28 from line 7”. Part II also carries this heading: “Expenses. Enter expenses for business use of your home only on line 30.” Lines 28 and 29 are explained on the Schedule C lines 27a to 29 page and line 30 on the Schedule C line 30 page. The overall form is explained on the Schedule C (Form 1040) page, and the return it attaches to is the Form 1040.
Edition and line numbers
This page reads the 2025 Schedule C (Form 1040) and its 2025 instructions, the current files irs.gov served on 2026-10-18. They are the files for the tax year 2025 return, filed in 2026. The schedule’s heading says “Attach to Form 1040, 1040-SR, 1040-SS, 1040-NR, or 1041”. Check the tax year printed on the schedule you are filling in and use the line numbers on that year’s schedule, because a different year’s schedule can number or word its lines differently.
Common mistakes
- Deducting your own labor as a repair cost. The instructions say “Do not deduct the value of your own labor.”
- Deducting a replacement as a repair. The instructions say “Do not deduct amounts spent to restore or replace property; they must be capitalized.”
- Expensing long-lived equipment as supplies. The instructions say “if their usefulness extends substantially beyond a year, you must generally recover their costs through depreciation.”
Related: Schedule C (Form 1040), Form 4562, and Form 1040.
Sources
- Instructions for Schedule C (Form 1040), Profit or Loss From Business (2025): https://www.irs.gov/pub/irs-pdf/i1040sc.pdf
- Schedule C (Form 1040), Profit or Loss From Business (2025): https://www.irs.gov/pub/irs-pdf/f1040sc.pdf
Read from the IRS documents linked above on October 18, 2026. General information, not tax advice. Your own facts decide the outcome, and a preparer, the account provider or the IRS is the right place to confirm anything consequential.