Markets
The Mexican Peso Has Lost About 6% Against the Dollar in Two Weeks
USD/MXN rose in nine of ten sessions between September 22 and October 1, reaching 18.38. The peso is now weaker than it was at the start of 2026, and it has lagged other emerging-market currencies.
For most of 2026 the Mexican peso was one of the steadier stories in currency markets. In mid-September, the dollar bought about 17.2 pesos on Binance's USDT/MXN market — a level the pair had been drifting around for weeks. That changed quickly. The pair closed at 17.21 on September 21 and at 18.30 on October 1, a rise of about 6.3% in ten days. Only one of those ten daily candles, September 25, closed lower than the day before.
The move came in a staircase rather than a spike. USD/MXN climbed through 17.5 on September 23, touched 17.75 on September 24, crossed 18 on September 29 and peaked at 18.38 in the 15:00 UTC hour on October 1. That October 1 close was the peso's weakest since December 3, 2025, and above the 18.10 at which the pair ended last year — so after a strong first half, the peso has now given back all of its 2026 gains against the dollar on this measure.
Some of this is the dollar rather than the peso. The euro, the South African rand and the Colombian peso all lost ground over the same stretch, and EUR/USD closed October 2 at its lowest level since May 2025. But the Mexican currency has fallen further than most: since September 15, the dollar has gained about 6% against it, compared with roughly 2.5% against the euro and the rand and about 4% against the Colombian peso. The price data alone can't tell us why, and we haven't tied the move to a single announcement.
The pair has been calm since. It slipped back to 18.18 on October 2 and barely moved on Saturday, closing at 18.17, as it usually does when the main currency markets are shut. A caveat on the source: USDT/MXN is priced against a dollar stablecoin and trades a few million dollars a day, a tiny fraction of the interbank market, so individual candles — particularly wicks in thin hours — can be noisier than the main market. The two-week trend, though, is large and consistent enough to stand on its own. The 18.38 high and the 17.90 area, where dips stalled on September 30 and October 1, are the levels to watch when trading resumes.