All estimated tax payments were made on time.  Form 2210 has no place to enter estimated tax payments. My client is getting almost $2,000.00 in refund. With or without Form 2210 the return rejects. Both taxpayers are retired, draw social security and interest and capital gain on a note. Each year their actual income decreases. I have tried to e-file with & without Form 2210 & rejected both ways. The reason given is Form 2210. Why is this return rejecting from the IRS?