SMS content rules — links, length, and blocked words

Why texts are screened

Mobile carriers aggressively filter bulk messaging, and a single non-compliant blast can get a sending number blocked — silently killing delivery for every future message. To protect your campaign, Pledgix checks each SMS against carrier rules twice: once as you compose (so you get instant feedback) and again on our servers just before sending (so nothing slips through). A message that fails shows a Carrier Compliance Alert naming the exact problem.

Rule 1: Links

Only Pledgix links are allowed — pledgix.com and the platform's own campaign addresses. External links are one of the strongest spam signals carriers look for, and shortened links (bit.ly and friends) are worse. If your message contains a web address pointing anywhere else, it will be blocked before sending, and the alert tells you which link was the problem. (One exception: a campaign whose manager has configured a custom donation destination — for example in the Call Center — may link to that specific host in those messages.)

The good news: you rarely need to type a link at all. The Donation URL and Team URL variables insert compliant campaign links automatically, personalized per recipient.

Rule 2: Restricted words

Carriers prohibit bulk messaging about certain topics regardless of context — adult content, hate speech, firearms, gambling, drugs, loans and cryptocurrency, scam-associated phrases like "free money," profanity, and violent language. Pledgix screens for many of these terms in multiple languages (including English, Hebrew, Russian, Spanish, and French), but the filter isn't exhaustive — passing the check doesn't guarantee a message meets every carrier rule, so keep restricted topics out of your texts even if no alert appears.

If a blocked word is detected, the alert quotes it so you can rephrase. Occasionally an innocent phrase trips the filter — if you believe a block is a false positive, adjust the wording, or contact the Pledgix team if you can't find a workable phrasing.

Rule 3: Length and segments

Text messages are billed and delivered in segments:

• A message using standard Latin characters fits 160 characters in a single segment. Once a message runs longer, part of each segment is used for stitching data, so multi-segment messages hold 153 characters per segment.
• Emoji, Hebrew, Russian, or other non-Latin characters switch the whole message to a different encoding: 70 characters for a single segment, 67 per segment for longer messages. The composer shows a warning the moment this happens.
• A few otherwise-ordinary symbols — { } [ ] ~ ^ \ | € — count as two characters each in the standard encoding.
• Longer messages still deliver — phones stitch segments back together — but each segment counts as a separate message for cost and, on older devices, very long texts can arrive split.

The circular counter in the Compose SMS card tracks your remaining characters and current segment count in real time, using the same math the carriers bill by.

Tip: One emoji can triple the cost of a 150-character message by forcing it from one 160-character segment into three 67-character segments. If budget matters, keep blasts emoji-free — or keep the whole message under 70 characters.

What good campaign texts look like

• Identify yourself immediately: "Hi, it's the Riverdale Fund —" beats a mystery message.
• One idea, one link: a short ask plus your donation link.
• Personalize: variables like Team Name make a blast feel individual.
• Make opting out easy: a recipient who replies STOP is suppressed automatically, platform-wide. For requests that arrive any other way ("please stop texting me"), add the number to your Do Not Call list yourself (see Do Not Call and opt-out management).

Related articles

• Sending SMS to your teams
• Texting beyond your team roster
• Consent, quiet hours, and compliance