I believe you have had four jobs so far this year. You have 3 part time jobs now. I suggest you prepare a schedule with the earnings and withholding to date on all jobs. Then add the projected income and withholding for the 3 part time jobs for the balance of the year. You can use the TurboTax 2023 Tax calculator to estimate your 2024 tax liability. https://turbotax.intuit.com/tax-tools/calculators/taxcaster/. The amount you compute will not be exact since it is using the 2023 rates, but it will give you an idea of the general tax liability. You can then deduct the amount withheld to date plus the amount that you estimate will be withheld for the rest of the year. That will give you an estimate of the balance of the tax due. The estimate of the shortage should be paid in quarterly installments.
