IRS requires you to estimate your total tax for the year and pay as you go.
you can base your estimate on prior year's tax, or 90% of this year's tax, whichever is smaller.
each quarter your estimated tax paid and withheld must be at least 25% of the estimate, even if your income is uneven, this is the simpiified method.
if your estimate is based on this year's tax and turns out to be wrong you may be penalized.
you can compensate by overestimating.
if your estimate is based on prior year's tax, you know that when you file by April 15, which is also the first estimated tax payment due date. How convenient.
Since your spouse has W-2 withholding you can subtract that yearly amount to arrive at Estimated Tax payments.
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If your quarterly withholding and estimates for 2024 are at least 100% / 4 = 25% ( 110% / 4 for certain high income taxpayers) of your 2023 tax, there will be no penalty on your 2024 tax return, regardless of any jump in income.
Your total tax includes SE tax.
@ChrisP81
