What is the least amount i can put for a babysitter without them having to pay taxes?

[SweetieJean]

You must report the actual amount, and they must claim the actual amount.

No one here is going to help either of you commit tax fraud.

[macuser_22]

Whether the sitter pays tax or not depends if the sitting takes place in your home which, in most cases, makes them a house hold employee.    In that case, if the sitters total income is more then that filing requirement amount for their filing status they would have to file a ta return.  Whether they pay any tax or not, depends on all of their income.  You have not control over that, since it depends of income from all sources.

If the sitting takes place in the sitters home, or the sitter is treated as self-employed, then the maximum that they can earn from all sources, not just you, is $399.    $400 or more of self-employed income requires a tax return an paying some tax.