Hello, 

Thanks for your post. 

What sort of deliverability issues are you seeing?

Depending on the growth your SMS list has experienced it may be a throughput issue. Here is our guide for choosing the right SMS numbers. 

For long codes we recommend 1 number for every 200 SMS subscribers on your list.  Short codes have much higher throughput and are subject to less filtering than long codes, however short codes are also more expensive than long codes. 

If you are anticipating SMS being a large part of your marketing strategy moving forward you may consider moving to short codes for some of the advantages, but more often than not it is not a necessity to move to short codes. 

Best,

Bill

Thanks @bill.hamilton . Most of the deliverability issues are categorized as carrier violations.

Hi @Suz_G-Form - From what I understand, many carriers have stricter filtering policies for long numbers than they do for short codes. In particular, T-Mobile and Sprint are more proactive about filtering A2P (application to person) traffic, so it can make it so that the delivery of messages to Sprint and T-Mobile phone numbers is inconsistent. However, if you are experiencing deliverability issues with your long number, you may want to look into getting a verified toll-free number, if not a short code. You can also find more details about SMS Filtering in this article here. 

Thanks, 
-Cass.