Fed hike odds at 83% on Polymarket ahead of September 16, with Bitcoin and XRP already pricing the move

Prediction market Polymarket priced a 25 basis point Federal Reserve hike at the September 15-16 FOMC meeting at 83% as of September 12, 2026, up from roughly 30% before the Jackson Hole symposium and about 50% before the August CPI release. Bitcoin ($BTC) and XRP ($XRP) have been absorbing that repricing for two weeks. The next concrete event is the Fed decision on September 16.

How the odds got to 83%

August's core CPI print came in at 0.3%, one-tenth above the 0.2% consensus, while the headline matched estimates. That hotter-than-expected underlying read drove the Polymarket probability from 50% to 83%, the largest single jump in the cycle. On August 31, 2026, Barclays flipped its forecast and now calls for back-to-back 25 basis point increases. Chair Kevin Warsh's Fed has sat on the 3.75% upper bound through five straight meetings, with no cuts in 2026 and no change since December 2025, when the rate stepped down from 4.5% in September 2025. A hike on September 16 would mark the first increase since 2023.

Treasury yields have been moving ahead of the decision. The 10-year closed at 4.95% on September 10, 2026, its highest in a year, 0.25 percentage points above where it sat a month earlier and up 0.12 percentage points in that session alone.

What the setup looks like for $BTC and $XRP

Bitcoin was at $77,293.66 on September 12, 2026, 3.26% lower on the week and 33.48% below its level from a year ago. Its one-month gain reads 21.77%, though the source of that move is August's low base. Bitcoin now tracks rate-sensitive assets more closely than at any point on record, so the Fed's reach into crypto arrives faster this cycle than in any prior one. XRP sat at $1.37 on September 12, 2026, off 3.91% for the week and 56.31% below its level from a year ago. Without the spot ETF footprint or corporate treasury demand that supports Bitcoin, XRP's buyer base skews toward retail and short-term traders, and it tends to swing harder on Fed days in either direction.

Both coins have been sitting with these odds for two weeks: Bitcoin above $77,000 and XRP above $1.30 through the week's yield move. A delivered 25-basis-point hike likely produces a modest reaction. The 18% hold scenario carries the larger surprise potential, as an unexpected pause would remove the tighter policy already baked into both coins. Polymarket's residual probability of a 50 basis point move would, based on historical patterns, hit XRP harder than Bitcoin.

The statement lands on September 16. Watch the 10-year against its September 10 close of 4.95%.