Anyone know of a reliable website to figure out this bus schedule? ADO says there are only two buses on July 26. Can that be right? www.ticketbus.com.mx never works. At all.

One of the ADO sites is for GL service -- that's their top service, above first class. Sometimes that's the only ADO site available. There are only about two of those GL buses a day, but there are many regular first class ADO buses daily.

The Ticketbus site works fine for me, in both Spanish and English. I'm using the Firefox browser. Sometimes a little slow, but otherwise a great site. It shows 20 ADO buses this coming Monday from Cancun to Chetumal (256 pesos or about US$19) and 18 ADO buses from Playa del Carmen to Chetumal (216 pesos one-way).

Note that you will get results for four day parts, Dawn, Morning, Afternoon and Night, and you'll have to click on each of those to get the full results. Note also that the Playa bus station with service to Chetumal is Playa del Carmen, Qroo not Playa del Carmen Alterna. (which is the older station near the beach).

ADO buses are excellent.

I know what you mean, BSprout. That site usually works well, but I was using it yesterday, and it wasn't working at all on Firefox or IE!

In addition to what Lan said about the tabs, it doesn’t seem to work so well when you look up times more than a couple of weeks further on from today’s date. But the schedules don’t vary much, and the schedules for one day will probably be the same as every other day of the week.

Here's the link to the ADO site:
http://www.adogl.com.mx

And here is some information from my website:

At the Chetumal ADO terminal, get an ADO Express bus to Playa del Carmen; departure times are 06:30, 08:30, 10:30, 12:30, 13:30, 14:30, 15:30, 16:30, 18:30, 20:00 & 00:45. The trip takes about 4.5 hours and costs MX$204 for Primera Class (as at June 2009).

The bus arrives at the bus terminal at Avenida 20 and Calle 12 (Terminal Alterna). If you want to continue to Cancun airport immediately, get a taxi (MX$20 or 30) or walk to the other bus terminal at Quinta Avenida and Avenida Juarez where you get the ADO airport shuttle bus to Cancun airport. The trip takes 1 hour and costs MX$90.

Link: http://belizebus.wordpress.com/

You need to use Firefox to get it to work.

My default browser is Firefox, and the ticketbus site sometimes works fine, and other times not so fine regardless of whether it's a slow BTL internet connection or a faster connection.

Yesterday was one of the not so fine days. Today, it's working fine. It's like a box of Forrest Gump chocolates, you never know what you're gonna get!