SMS Attachment Size Limits

July 30, 2024•1 min read

SMS carriers and have attachment file size limitations to prevent deliverability issues and to make sure that their servers are not overloaded with hefty file sizes while millions of people around the world use their services to send SMS.

SMS

We support up to 10 attachments, as long as the total size of the message body text and all attachments is less than 5 MB.

Carriers also have limits. The average is 300kb-600kb and can go up to 3.5MB for tier 1 providers (AT&T/Verizon, etc.)

Here are the Carrier Attachment Size limits for some common US Carriers:

The file sizes above will generally be passed along to the wireless carriers. However, due to differences in handsets, file types, and transcoding, we recommend you send attachments no larger than 500KB to ensure the best chance of delivery.

These image file types are supported:

jpeg
png
gif

As of May 2021, there is an issue with Toll-Free MMS file size support; for these numbers, you must ensure that any attachments (including images) are 600kb or smaller.

Moe Ameen | BILT CRM

Moe Ameen is a real estate investor, software creator, and general over-caffeinated human who somehow made automation cool (or at least tolerable). He built a cutting-edge real estate CRM because manually chasing leads is so last century. Specializing in creative finance, deal structuring, and making things unnecessarily efficient, he helps investors close more deals while doing less actual work. When he's not automating the real estate world, he’s probably pretending to work while staring at spreadsheets or convincing himself that buying another domain name is a good idea.

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