For tax year 2015 we had an income of $64,000. Besides the $64,000 we sold some mutual funds and the capital gains from that was $98,000. I was under the impression that since we (married filing jointly) were under $74,900 (15% tax bracket) on income before the capital gains, that we wouldn't have to pay any capital gains tax, but our tax preparer said we did. Was that correct?

Thanks

Yes he , the tax pro was correct; since you need to include your LTCG of $98K on your Sch D/ From 8949 , you will list the security, the gross proceeds, the basis, and you will subtract the basis from the proceeds to enter the net gain for the transaction. Once you total everything up, you should show the gain, which then carries over to your 1040 line 13. You need to s Complete the Qualified Dividends and Capital Gain Tax Worksheet in the instructions for Form 1040, line 44