How to handle prepayments, rounds, and discounts when splitting

The prepayment problem

Say one person already paid $40 for the group's ride or covered the deposit. They shouldn't owe as much on the tab — or the group may owe them. The key is to credit the prepayment against the split, not to just remember it later and hope it nets out.

Three ways to credit a prepayment

Pick the mode that matches what actually happened. The important thing is that the prepayment is accounted for in the math, not in someone's memory.

• Reduce what they owe: subtract the prepaid amount from that person's share, and they only pay the remainder.
• Leave their share, note the group owes them: keep their tab share intact and record a refund the group owes them back — useful when the prepayment was for something separate from the bill.
• Take them out of the split: if their prepayment effectively covers their participation, hide them from the split and reduce the overall total accordingly.

Someone bought a round

A bought round is really a prepayment in disguise: one person paid for items that several people consumed. You can either assign those drinks to the people who drank them (and credit the buyer for having paid), or, among close friends, let rounds wash out over the night. For a one-off group, assign and credit.

Coupons and group discounts

A whole-bill discount (a $20-off coupon, a happy-hour percentage) should be distributed proportionally, the same as tax and tip — everyone's share shrinks in line with what they ordered. Applying the full discount to one person's total just shifts the savings to whoever happens to be holding the coupon.

Per-person comps

Sometimes the discount belongs to one person — the birthday entrée is on the house, or a manager comped a specific dish. In that case, apply it to that person's items only, and make sure the amount is absorbed correctly so the rest of the table still adds up to what was actually paid.

Keeping the total balanced

The trap with all of these is ending up with per-person amounts that don't sum to what hit the card. Tab Tender supports prepayments (in all three modes), weighted and shared items, and both whole-bill and per-person discounts — and always reconciles the parts back to the real total so the split stays honest.