Commission split is usually the first number new agents ask about, and usually the number that's most misunderstood.
Traditional splits
A traditional split — commonly 70/30 or 80/20 in the agent's favor — means the brokerage takes a percentage of every commission you earn, with no separate desk fees. Splits often improve as you close more volume in a year.
"100% commission" brokerages
These brokerages let you keep the full commission on paper, but charge a flat monthly desk fee and a per-transaction fee instead. Whether this is actually cheaper depends entirely on your expected volume — do the math against a traditional split at your realistic first-year transaction count, not an optimistic one.
Caps
Some brokerages cap the total amount you pay them in a year — once you hit the cap, you keep 100% of commission for the rest of that period. This rewards higher-volume agents and matters less if you're doing a handful of deals a year.
What the split doesn't include
MLS dues, E&O insurance, and marketing costs are often separate from the split entirely. A brokerage with a great split but no support infrastructure can end up costing more in time and marketing spend than one with a slightly worse split and real lead flow.