Charge for going through cbx to San Diego?

clear

Yes, $ 20 per person

In my experience, it has been cheaper to buy the pass before crossing (as Onceinawhile says, 20 USD) than to buy it with the airline, the requirement to use the crossing is that, to have a boarding pass or proof that you flew.

You can buy it through the Mexican flight airline for example Volaris, Aeromexico or Viva Aerobus, or pay at the time of the crossing with the great advantage of saving time, space and comfort.