I mailed my tax return a month ago from Spain and I don't know if the CRA has received my documents, is there any way to find out without calling them?

CRA accepts faxes for those living in other countries. If you mailed it in, once it has been received and assessed it will take another long time to receive your Notice of Assessment by mail with your cheque if you are getting a refund. In Canada alone when we send our return by mail it can take up to 6-8 weeks. 

You can contact the CRA from another country by making a 'collect call" which means that you dial zero for an operator and give them this CRA phone number-1-613-940-8495, you stay on the phone and wait until they reach someone and they at this end will expect the charges for the call then you will be put through to speak to them. 

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