FedEx, USPS or some other service for TECO

I need to mail documents to TECO, and then include a prepaid envelop for them to mail the documents back. The documents would be mailed within the US. I am thinking of using FedEx, since I definitely want tracking. In normal times USPS Express Mail could be okay, but I think since USPS is in trouble right now, USPS would be less reliable. What have people used to mail documents within the US?

unless you have a fedex account that gets corporate discounts it’s not worth it. the post office sells priority mail stamps (cost me 7.75 end of july 2020) and you can ask for a tracking number sticker that’s been generated but not activated until it ships.

Thank you very much. I did not know we can buy tracking in advance

UPS lost my documents twice. Their volumes are extremely high due to Amazon shipments during covid. I highly recommend FedEx within the U.S. if your TECO office accepts FedEx. They specialize in important documents, versus ordinary mail or packages.
See this link about getting a return envelope.

I would recommend that you ask your TECO office if they have a preference.

For instance, TECO in Houston expressed strongly that I should not use FedEx for my special entry visa documents last April. The official I worked with told me that Houston would accept UPS and USPS, but not to use FedEx.

@bojack, that is very interesting. Thank you. I edited my post to reflect the point you made.

TECO Houston now accepts FedEx for the return package. https://www.roc-taiwan.org/ushou_en/post/1741.html

If a TECO office prefers UPS but accepts FedEx, I still think FedEx is better. To lose original passports and birth certificates can create a lot of hassle.

Two months after the package was lost by UPS, it was found by UPS and sent to TECO. Interestingly enough, UPS never sent me an email indicating that the package had been found.