Polymarket pays holding rewards on eligible positions — yield for simply holding shares in qualifying markets. This page lists every eligible market with its live APY, so you can size a position around the actual return rather than a headline rate.
Combine it with 99%+ bets to stack a near-certain payout with reward APY, and use the split/merge tools to build full sets efficiently.
Rewards accrue per day held and are paid in pUSD. Combine with a 99%+ position to stack the reward APY on top of the resolution spread.