IRS Form 990C vs. 1120 vs. 1120C
For the 2006 filing year, the Internal Revenue Service changed the cooperative tax reporting form from 990C to 1120C. Almost immediately, problems arose. The IRS was not set up to accept tax deposits for form 1120C so the deposits were recorded as 1120. The IRS assured us that they would automatically reclassify 1120 payments to 1120C for all taxpayers that had previously filed form 990C.
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