For decades the polite answer was "nothing — the seller pays your agent." It was never quite true, since the money came out of a sale price you were financing, but it was true enough that nobody read the fine print. Since the industry settlement took effect in August 2024, the polite answer is gone: before an agent can tour homes with you, you sign an agreement that states what you owe them, and that number is yours regardless of what any seller later offers.
So the real answer has three parts. First, the rate in your representation agreement — a percentage of the purchase price, a flat fee, or occasionally an hourly rate. Second, whatever concession the seller offers toward it, which is negotiated deal by deal and can be anything from the full amount to nothing. Third, the difference, which many agreements make your personal obligation, in cash, at closing.
The three-sentence version of the new rules
Your agreement with your agent sets what you owe your agent. The seller may offer a concession that covers some or all of it. Nothing forces those two numbers to match, and the sentence in your agreement that handles a mismatch is the most expensive sentence in the document.
None of this means agents are overpaid, and none of it means yours is. It means the number is now visibly yours to agree to — which is new, and better, and only helps if you actually read it before signing.
What moves and what does not
The rate itself is set by agreement between you and the agent — there is no legal standard rate, and it is unlawful for agents in a market to fix one. The term length, the protection period after it ends, whether the agreement is exclusive, and what happens on a shortfall are all terms of a private contract, which is to say: they are whatever the two of you sign.
An agent who explains their fee and holds it is not doing anything wrong. An agent who says the fee is standard, required, or not worth reading about is telling you something useful too.