Chinese languages

I'm needing to send business related mail from the U.S. to Mainland China, and need to know how to correctly address the envelopes. Should I use mostly Chinese characters, followed by the region and the postal code in English, or do I need to write it out in both English and Mandarin?
Any experienced help is appreciated.

When I send to HK and Japan I use Chinese/Japanese for the local address etc., but you have to put down country and postal code for the US mailing system.
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think it would be better if you could address them all in chinese. But you have to put down "CHINA" or "TAIWAN" at least for the sake of the mailman in the states

: I'm needing to send business related mail from the U.S. to Mainland China, and need to know how to correctly address the envelopes. Should I use mostly Chinese characters, followed by the region and the postal code in English, or do I need to write it out in both English and Mandarin?
: Any experienced help is appreciated.
: I've had plenty of mail sent to me in China and all of the address was in English and Pin Yin. I haven't had any problems with this. Just make sure your Pin Yin is correct.

When My husband wanted to send letters to his mum in China, he wrote the address in Chinese characters, with just To China in English. But this was from England instead of America. Also he is chinese, so it is easier for him to write chinese characters. .. and she got the letter.

: I'm needing to send business related mail from the U.S. to Mainland China, and need to know how to correctly address the envelopes. Should I use mostly Chinese characters, followed by the region and the postal code in English, or do I need to write it out in both English and Mandarin?
: Any experienced help is appreciated.
:

I've had plenty of mail sent to me in China and all of the address was in English and Pin Yin. I haven't had any problems with this. Just make sure your Pin Yin is correct.