Per Diem Rates from the U.S. General Services Administration
Search by city, state or ZIP code, or by clicking on the map. You can also use the new per diem tool to calculate trip allowances
Rates are set by fiscal year, effective October 1 each year. Find current rates in the continental United States ("CONUS Rates").
Changing from Accrual to Cash basis - Form 3115
If you currently use the accrual method and if your business qualifies to use the cash method under Revenue Procedure 2002-28, you can apply for an automatic change in accounting method by filing Form 3115 with your return.
The IRS will grant automatic consent to an accounting-method change as long as you file Form 3115 with your return. You will have to make a Sec. 481 adjustment in the change year.
Internal Revenue Code Section 481 deals with adjustments required by changes in the method of accounting (ask your accountant about this).
If the change creates an increase in income, you're allowed to spread the income over a four-year period, however, a loss must be taken immediately.