Topics What you can deduct How much you can deduct When to deduct Not-for-profit activities Useful Items Publication 334   Tax Guide for Small Business 463   Travel, Entertainment, Gift, and Car Expenses 525   Taxable and Nontaxable Income 529   Miscellaneous Deductions 536   Net Operating Losses (NOLs) for Individuals, Estates, and Trusts 538   Accounting Periods and Methods 542   Corporations 547   Casualties, Disasters, and Thefts 587   Business Use of Your Home (Including Use by Day-Care Providers) 925   Passive Activity and At-Risk Rules 936   Home Mortgage Interest Deduction 946   How To Depreciate Property Form (and Instructions) Sch A (Form 1040)   Itemized Deductions 5213   Election To Postpone Determination as To Whether the Presumption Applies That an Activity Is Engaged in for Profit