Attach Images to Text Messages Using Custom Values

If you reuse the same picture across several workflows, store its link once as a custom value and attach that value to your text messages. When the image changes, you update one place instead of every workflow.

Create the custom value

1. Open Settings > Custom Values.
2. Click + Add Custom Value.
3. Name it clearly, for example "Promo image URL".
4. Paste the direct link to the image file and save.

Attach it in a workflow

1. Open the workflow containing your Send SMS action.
2. In the attachment area, paste the custom value's merge tag.
3. Save the action and publish the workflow.

Size and format limits

Carriers, not Vendi Today, decide how big a picture message can be, so keep files small. Approximate ceilings for US long-code numbers are:

Toll-free numbers are generally capped near 0.6 MB. Use JPEG, PNG, or GIF files only.

If the image doesn't arrive

• Make sure the link contains no spaces or stray characters.
• Check that the link opens directly to the image when pasted into a browser, ideally in a private window.
• Compress the file below the smallest carrier limit you need to support.
• Confirm the merge tag is spelled exactly as in your custom values list.

Good to know: Aim for under 0.5 MB so one image works for every carrier, and use the same custom value across workflows to make seasonal updates a one-step job.