Crossing at San Luis for a dental appointment

Walking is usually much faster than driving

This is the single most useful thing to know about the San Luis crossing, and almost nobody says it clearly. The vehicle queue and the pedestrian queue are completely separate, and they are rarely similar.

We have been recording the published figures for both every hour. It is common to see the vehicle queue running an hour or more while the pedestrian queue sits at five minutes. Parking on the Arizona side and walking across can turn a long wait into a short one, in both directions.

You can check what both queues are doing right now on our border wait times page before you set off.

The clocks do not change

Sonora keeps the same time as Arizona all year. Neither side observes daylight saving, so unlike most of the border there is never an hour to add or subtract. An appointment at 3pm is at 3pm on both sides, in every month.

That removes the most common cause of missed appointments along this border, but it surprises people who have crossed elsewhere and are braced for a change.

Timing the appointment around the queue

The wait to come back into the United States varies enormously by hour, and the pattern is reasonably consistent. What matters is not when your appointment starts but when it ends, because that is when you join the queue.

From the readings we have collected so far, the middle of the morning tends to be among the slowest times to cross northbound, and late evening among the quickest. That pattern will firm up the longer we measure it, and the live page always shows the current picture rather than an average.

If your treatment needs ninety minutes, work backwards. An appointment that finishes into the worst part of the day can add more time to your trip than the treatment itself took.

Before you go

Check what documents you need to re-enter the United States, and check it with U.S. Customs and Border Protection rather than with us. Requirements differ by citizenship and by whether you are walking or driving, and they change. It is not something to take second hand.

If you are driving, be aware that Mexican authorities and your own insurer have their own requirements for taking a vehicle across. Again, confirm that with them.

Once you are across

We are on Avenida Álvaro Obregón 1407, between Calle 14 and Calle 15, a few minutes from the crossing. There is a photograph of the building and turn by turn directions on our directions page, which is worth a look before you arrive rather than while you are driving.

Our hours are Monday to Friday, 9am to 2pm and 4pm to 7pm, and Saturday 9am to 2pm. Those are Arizona hours too, for the reason above.