Do texts to international cell phones cost the same as texts to cell numbers in the same country?
International rates vary depending on the country you are sending to and the carrier you are with. Almost every carrier has a international plan that you can add on to your monthly bill, the cost varies per carrier, that will help reduce the cost some.
Another method is to use programs and apps such facebook messaging, hangouts, skype, facetime, and several others that will allow you to communicate with people internationally and not cost you anything extra. This is because they use data from WiFi rather than your mobile carrier. This is as long as you are connected to a WiFi network.