SMS messages allow 160 characters. Long URLs can use 50+ characters, increasing costs and reducing message space. Omnisend shortens links to save characters and track clicks.
Links are replaced with unique short URLs (e.g., 0snd.com/c/XXXXXX) that use ~15 characters, preserving message space and enabling click tracking. Each link is unique per recipient and appears only when the message is sent, not in the editor.
💡 Tip: Use Branded SMS Short Links to replace 0snd.com with your own domain (e.g., yourbrand.com) for better trust and brand recognition.
How Omnisend Shortens Links Automatically
Every time you add a link to your SMS message, Omnisend replaces it with a unique shortened link during send time.
Regardless of your link's length, we replace it with this pattern:
Automation SMS:
0snd.com/a/XXXXXXCampaign SMS:
0snd.com/c/XXXXXX
Link structure breakdown:
Domain:
0snd.com– The shared domain we use to shorten and track links. To reflect your brand, set up Branded SMS Short Links, replacing0snd.comwith your own domain (e.g.,sms.yourbrand.com).Link type:
/a/or/c/– This separates automation and campaign links from unsubscribe links:a = Automation link
c = Campaign link
Unique identifier:
XXXXXX– A unique code per recipient that tracks who clicked the link.
💡 Recommendation: Start your SMS with your brand name (e.g., "ACME: Flash sale ends tonight!"), so recipients recognize you immediately, especially in countries where custom sender names aren't supported.
How Link Clicks Are Tracked
Shortened links enable automatic click tracking for your SMS reports. When a recipient clicks, we record the event and attribute any resulting sales to that SMS.
UTM parameters
We add UTM tags to every shortened link so you can track performance in Google Analytics. The structure differs between campaigns and automation workflows:
For SMS Automation:
utm_source={{presetName}}– The name of your automation (e.g., Abandoned Cart, Order Confirmation). This value changes if you rename the automation.utm_medium=sms– Always remainssms.utm_campaign={{flowBlockID}}– The ID of the SMS block in your workflow. If your automation has multiple SMS blocks, this helps identify which block's link was clicked. You can find block IDs in Reports.contactID={{contactID}}– Encoded recipient ID for attribution.
For SMS Campaigns:
utm_source=The name of your campaign.utm_medium=sms– Always remainssms.utm_campaign=The campaign ID.contactID={{contactID}}– Encoded recipient ID.
These parameters help you compare SMS performance across workflows and platforms.
💡 Custom UTM tags: You can also add your own custom UTM parameters for more personalized tracking in both campaigns and automation workflows.
Understand Character Count
SMS messages support up to 160 characters. Longer messages are split into multiple SMS and cost more.
How the character counter works:
The counter in the SMS editor shows the character count before link shortening.
If your message contains only text, the counter reflects the exact number of
characters. When you add a link, the counter counts the full URL, which may be longer than the final link sent.
Example:
Original link:
https://www.omnisend.com(24 characters).Shortened link:
0snd.com/c/xxxxx(15 characters).Saved: 9 characters
Result: You see 24 characters in the editor, but the actual sent message uses only 15 – saving space and cost.
Note: Special characters (emojis, accents) reduce the limit to 70 characters per SMS. Learn more about SMS character counting.
When to Disable Link Shortening
You can disable link shortening in campaigns or automations if you prefer to display the full URL. For example, the link https://omnisend.com/cart will appear exactly as written.
However, disabling automatic link shortening has several limitations:
No click tracking – Omnisend will not track clicks or attribute sales to this SMS message.
No automatic UTM parameters – Performance data will not be tracked unless you add UTM parameters manually.
Higher character count – Long URLs increase the message length and may push it over the 160-character limit, causing the SMS to split into multiple segments and potentially increasing costs.
⚠️ Important: Never use third-party link shorteners (e.g., bit.ly, TinyURL). Carriers flag these as suspicious and may block your messages.
FAQ
Why do I see my full URL in the editor but a shortened link in preview?
Link replacement happens when your message is prepared for sending, not while you're creating it. You'll see your original URL in the editor, but recipients (and preview/test messages) will show the shortened version like 0snd.com/c/XXXXXX. This is expected behavior.
Will old links still work if I switch to Branded Short Links?
Yes. Previously sent links using 0snd.com will continue to work. Only new messages will use your branded domain.
What happens if I disable link shortening after sending messages?
Nothing. The setting applies only to future messages. Already-sent messages aren't affected.
Why is my SMS link redirecting to the wrong page or showing a 404 error?
If your shortened link doesn't redirect correctly, verify that:
Your original URL includes
https://and is correctly formatted.The URL works when pasted directly into a browser.
You're not using another link shortener (e.g., bit.ly) alongside Omnisend's feature.
If the issue persists, contact our Support Team with your campaign ID and the shortened link.
If you have any questions, please contact our Support Team via in-app chat or email us at [email protected].