You budget against your floor, not your average. Figure out the lowest month you can reasonably count on, build your regular life to fit inside that, and treat everything above it as a separate decision rather than as spending money.
Averages Lie to You
If you sell twice a year, or your business swings hard by season, the average month doesn't exist. Build your life around an average and you'll be fine half the year and underwater the other half.
A rancher doesn't plan the winter around the best grass he saw in May. He plans around the worst month he's likely to get.
Give the Big Months a Job Before They Arrive
The danger with a good month isn't that it's temporary — it's that it feels permanent while it's happening. Decide in advance where a strong check goes: the cushion, the debt, the tax set-aside, the equipment fund.
Money with a job assigned before it lands is much harder to lose.
Set Taxes Aside as They Come In
If you're self-employed, part of every payment isn't yours. Moving that share out the same week it arrives prevents the worst surprise in small business.
What share, and how to handle estimated payments, is squarely a question for your CPA — the rules depend on your entity and your state.
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