For a worker making $40,000 or less, standard deductions often already wipe out federal tax obligations. But for someone in the $50,000 to $100,000 range, shielding $12,500 in overtime or $25,000 in tips could move them into a lower tax bracket.

The changes won’t happen all at once. Here’s when Americans can expect key provisions of the GOP tax and spending bill to go into effect.

The proposal, which Congress passed as part of the president’s tax-and-spending megabill, won’t eliminate taxes on tips entirely.