Polymarket open interest eases to $341M as trade count stays near 1.4M a day

Polymarket’s open interest eased to $341M, while its daily trade count remained near 1.4M, in the latest snapshot published Oct 13, 2026, at 7:54 AM ET. The figures show a smaller pool of outstanding positions alongside a broadly steady pace of transactions.

Trading volume slips over the latest 30 days

According to defirate.com, Polymarket recorded $4.6B in contract trading over Sep 13-Oct 12, 2026. That activity represented $2.3B in dollars paid—a separate measure from the stated contract volume.

Polymarket accounted for 5% of prediction-market volume during that period, according to defirate.com. Its volume was down 7% from the preceding 30 days, providing a softer backdrop to the latest open-interest reading.

The measures capture different aspects of activity: open interest tracks outstanding positions, trade count measures transaction frequency, and volume reflects trading over a period. With no prior open-interest figure or daily trade-size breakdown supplied, the snapshot does not establish the size of the open-interest decline or explain what drove it.

What it means for prediction markets

• Transaction frequency is not the same as exposure. A daily trade count near 1.4M can coexist with easing open interest; it does not, by itself, indicate growth in outstanding positions.
• Volume comparisons need consistent units. The $4.6B contract figure and $2.3B in dollars paid describe the same reporting period but should not be treated as interchangeable.
• The snapshot is platform-level, not outcome-specific. The 7% volume decline and 5% market share offer activity context, but do not establish a change in any individual contract’s implied probability.