As I noted earlier this week, today is the deadline for second quarter estimated tax payments. Since we’ve experience a relatively sizable uptick in income that’s not subject to withholding, we’re actually on our own for a good bit in the way of taxes. That being said, we can can actually hold back a good bit of this money until taxes are due next spring, allowing us to earn interest on the difference. The key here is to pay enough to avoid an underpayment penalty, but beyond that there’s no need to pay more than you want. Just be sure that you set aside sufficient funds to cover your tax bill when it comes due at the end of the year. In our case, we’re earmarking 50% of net profits to go into a special account to cover our SEP-IRA contributions as well as our state and federal tax liabilities (we make our estimated payments out of that account and will then pay the balance due from it at tax time).