China Post tracking number has standard formats as following:
format 1: the number starts with “R” and ends with “CN”, i.e. RR123456789CN, RI987654321CN
This is China Post registered airmail. Normally it will arrive destination in 2 to 8 weeks.
format 2: the number starts with “C” and ends with “CN”, i.e. CP123456789CN
This is China Post SAL (Surface and Airmail combined parcel). Normally it is much slower than airmail and might take up to 6 months to arrive.
format 3: the number starts with “U” and ends with “CN”, i.e. UA123456789CN,UE123456789CN etc
This is called China Post ordinary small packet(some people call it China Post ordinary airmail parcel). This is cheapest service. The tracking information is very very limited. You can only know shipment date, no further update after parcel leaves original post office.
China Post ordinary small packet is much cheaper than Registered Airmail especially for light weight item because it saves a lot of data entry labor. The arrival speed is similar to REGISTERED AIRMAIL.
format 4: the number starts with “E” and ends with “CN”, i.e. EE123456789CN, EA987654321CN
This is China Post Express Post Service(EMS). Normally it is much faster than airmail and might take one to four weeks to arrive. The price is also much higher than airmail.
format 5: the number starts with “A” and ends with “CN”, i.e. AS123456789CN
This is China Post EMS parcel. It is fastest and most expensive service.
format 6: the number starts with “L” and ends with “CN”, i.e. LK123456789CN, LN987654321CN,LM123456789CN,
This is China Post ePacket parcel. It is almost as faster as EMS and only a little bit more expensive than airmail.
All above tracking numbers can be tracked in https://track-chinapost.com
Since many big marketplaces such as ebay, aliexpress, amazon etc REQUIRE seller to ship goods with tracking number. Some China Post agents also provide some kind of mock “tracking number” for China Post Regular Airmail in order to fulfill the marketplace requirement.
Such kinds of mock “tracking numbers” have different forms, i.e CP1233456789, YW123456789YW,YC123456789YW, 123456789BJ,RI123456789EN,WD123456789CN …. Sometimes, those tracking number can shows some parcel pickup info and airport info in the agent’s own website. In most cases, the parcels from big agent such as Yanwen will arrive destination without any problem. However, these tracking number have nothing to do with China Post and China Post can not verify the authentic of the parcel shipment.
If you got such number over 30 days and can not receive the goods, you should open dispute to your seller.