Carrier Service API - Delivery Date calculation

New Member
3 0 0

Currently we encountered some issue on displaying estimated delivery date.

We followed the API document to send the min/max delivery date and calculated the date by business day.



In our case [UPS - 2nd Day Air] for example, the Delivery Timeline is 2 business days.


Hence we send the delivery date by the calculation below:

9/6(Sun) - checkout day (the day shows the checkout rate)

9/7(Mon) - Holiday (Labor Day)

9/8(Tues) - Day 1

9/9 (Wed) - Day 2

9/10 (Thur) - Estimated delivery date (2 days after)


Response date we send:




But at the end Shopify show [4 business days] on the checkout page and the client is confusing why this service needs 4 business day.



Looks like when Shopify didn't consider weekend/holiday when converting the date in to delivery day.

Is this a bug in Shopify side or should we send the date calculated base on normal day instead of business day?

Thanks a lot in advanced for any suggestions!

Shopify Partner
42 1 13

What app is it please?

New Member
3 0 0


This is Easyship App installed on Shopify store. 

I'm from Easyship Tech Team and we're looking at this checkout delivery date issue.

We followed the admin API and wondering what date should we sent for the carrier service.

Date calculated by business day or normal day.

Shopify Expert
4476 45 484

If my memory serves me correctly, ever since custom carrier was deployed, Shopify has never counted weekends properly with respect to business days, so you do indeed have to take that into account when you try and assign business days to your reponse returned to Shopify for display to the customer.


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