Will be arriving to Mexico City with KLM and then continue with a domestic flight. (AeroMexico). How much should we have time between the flights, just want to be sure we don´t fly from Mex without luggage...

Thanks, Ronny

1-2 hours ideal

I have made it in an hour many times. I bit more would be better in case you arriving flight is late. With one hour you have to hustle.

So you'll have to clear customs in Mexico City first.

My experience, at least clearing customs the other way around, is that once you've gone thru all the customs/immigration schtick you have to go back thru security as you are now in the general population again.

If I have to do that as I do returning to the US, I think 1 hour can be cutting it pretty thin.

two hours minimum

You most definitely will do Immigration in Mexico City. In March it took me perhaps 30 seconds but be sure your paper work is in order.
Now it is my understanding the YOU WILL go through Customs also in Mexico City. So I would allow at least 2 hours for this. It is now a long walk (including some stairs from The International landings to Immigration then to Domestic flights. I'd say a minimum of 7 to 8 minutes of brisk walking at least for this old guy.

Lo Siento! I meant to say IN SEPTEMBER you will also go through customs in Mexico City.