I will answer this question broadly for various jurisdictions, and also specifically for the US, given the OP's tax home:
Generally, for any tax jurisdiction
If your tax system relies on periodic prepayments through the year, and a final top-up/refund at the end of the year (ie: basically every country), you have 3 theoretical goals with how much you pre-pay:
- Prepay at least as much as you need to, to avoid penalties.
- Prepay as little as possible, so that you can earn income off the saved prepayments during the year. Remember - a tax bill at the end of the year means you held onto your money for as long as possible (which is good), and a tax refund at the end of the year means you were lending it to the government for free (which is bad).
- Save as much you need to, in risk-free savings, every paycheck, so that at the end of the year you can make the final top-up payment without incurring additional penalties for paying late.
Specifically, for the U.S.
All information gathered from here: https://www.irs.gov/businesses/small-businesses-self-employed/estimated-taxes. In short, depending on your circumstance, you may need to pay quarterly estimated tax payments to avoid penalties on April 15th. Even if you won't be penalized, you, may benefit from doing so anyway (to force yourself to save the money necessary by April 15th).
I have translated the general goals above, into US-specific advice:
- Your employer will withhold taxes on each of your paychecks. However, particularly if you work multiple jobs, these withholdings may not be enough to avoid penalties. Particularly, penalties may apply if (1) you owed any tax in the prior year; (2) You owe more than $1,000 in tax this year; (3) You paid less than 90% of the current year taxes you owed, in the current year; and (4) You paid less than 100% of last year's taxes, in the current year. This generally means that as long as your withholdings in the year are at least as much as last year's total taxes, then penalties will likely not apply. If that is not the case, you may need to make additional quarterly estimated tax payments (see the link).
- If you make unnecessary quarterly tax payments [unnecessary meaning that paying them will not eliminate any potential tax penalties at the end of the year - see note above], you are losing out on the ability to earn interest on that money before April 15th of next year.
- If you determine that you don't need to make quarterly tax payments, make sure you save money throughout the year to make your final payment on April 15th. If you forget about this, you run the risk of over-inflating your sense of your after-tax take home pay, and your living expenses may rise above what you can actually afford. Successful budgeting should include your true after-tax income, which includes saving for a final year tax payment, if relevant.