Can one report a plan on an accrual basis while one reports a 1040 on a cash basis?

[Guest Enda80]

Can one report a plan on an accrual basis while one reports the 1040 on a cash basis? If so, and the 1040 is on a cash basis, can one report contributions to the plan as a deduction on line 17 (as I recall, that represents the line for reporting contributions to a pension or retirement plan) even if they will be made after the tax return is filed, but before the extended due date of October 15?

[Mike Preston]

I think there may be some IRS guidance on this, somewhere. One can certainly report on the 1040 on a cash basis and report on the plan on an accrual basis. The pension deduction is the one accrual item that is allowed even if the taxpayer is cash. There is some controversy, as I recall, as to whether, once extended, a return can be filed recognizing a contribution made before the due date but after the filing date. That is, does the filing of an extended return guillotine any further extension? It think it does NOT. However, there is a ruling somewhere which says that once a return is filed, one may not THEN apply for an extension even if the filing would otherwise occur within the time frame when it was allowable. You may be confusing the two.