Cetes (Certificados de la Tesorería de la Federación) are short-term debt issued by the Mexican government at 28, 91, 182 or 364 days. You can buy them from 100 pesos at cetesdirecto.com with no commission. They pay roughly the same as a bank promissory note and are among the safest instruments available in Mexico.
Cetes are federal-government debt at 28, 91, 182 or 364 days, and among the safest instruments in the country. You buy them from 100 pesos at cetesdirecto.com, no commission and no intermediary. They yield about the same as a bank promissory note, sometimes a touch more, and the interest is government-backed.
What they're for in your financial life: they're the floor you measure any other investment against. If a «safe» product offers less than Cetes, the extra risk isn't worth it; if it offers much more, be suspicious. And they're the ideal parking spot for emergency money: safe, liquid every 28 days and earning.