Both options exist because they solve different problems. A bank lends more, at a lower rate, for longer — provided your profile fits. An online SOFOM lends less, at a higher rate, but the money lands the same day and they screen lighter.
When the bank wins
You have formal payroll (ideally six months tenure), a clean bureau, proof of address that matches your CURP. You need more than 30,000 pesos. You can wait two or three days for disbursement.
When the SOFOM wins
It's an emergency: a bill, a repair, a school payment due Friday. You need between 1,000 and 20,000. You need it today. Your bureau has old late marks or your income isn't formal.
The numerical gap
20,000 pesos over 12 months. Bank at 40% CAT: roughly 24,400 paid at the end. SOFOM at 180% CAT: roughly 38,500. The SOFOM costs an extra 14,000 pesos. If you can wait three days and you qualify at a bank, do that.
What almost nobody tells you
A well-paid first SOFOM loan, six months, is the fastest tool to start building history when you have none. Take a small ticket, pay on time, and by month six you can try a bank product with real approval odds. The trick is not staying in SOFOM out of inertia — use it as a bridge, not as home.