Please help —No “Large” Option Listed for USPS Flate Rate Box?

New Member
2 0 3

Hi there Shopify forums!

I have a large flat rate box I am trying to ship out ASAP. For some reason there is no option for this size, all other sizes are available but this one?

It’s very strange— I find the size, flat rate large 12 x 12 x 5.5, but it is available only for APO Army Adresses, I don’t think I should select this though for fear it will be returned back to me?

Should I go ahead and list under custom box ( even though this is a USPS flate rate?)  


I regularly use this box size for my large items and could possibly go through USPS shipping but I would love to go through this Platform as I keep many tracking numbers stored here and wouldn’t want them separated using outsourced shipping. Wondering if there’s any way we can add this box size into the shipping category. 


Any and all help is appreciated

3 0 7

I also have this question.  Where is the USPS Large Flat Rate Box option for shipping?

New Member
1 0 0

I also need to be able to ship USPS Large flat rate box but the option is not there. Please advise.