I always did my own taxes and it wasn't much trouble, until that is I bought a business and a commercial building and created an LLC and an S-corp. At that point I turned it over to a CPA and I would never even consider doing them myself again, even with the latest greatest tax software, waaaay too many things the software can't warn you about that a good CPA will. The S-corp is currently dormant but I still need the accountant to keep me oit of trouble. Even without significant tax law changes, year to year tax liabilities can be fickle, a couple years after buying the business one year I received a refund of about $16K, the next year I wrote Uncle Sugar a check for about the same amount, in addition to what had already been deducted. The curious thing for me was that be my reckoning the business and I made less money the latter year than it did the previous one. Go figure.