{"id":3021,"date":"2026-09-18T18:00:43","date_gmt":"2026-09-18T12:30:43","guid":{"rendered":"https:\/\/www.smsgatewaycenter.com\/blog\/?post_type=docs&#038;p=3021"},"modified":"2026-09-18T18:00:44","modified_gmt":"2026-09-18T12:30:44","password":"","slug":"what-is-cta-whitelisting-and-why-was-my-sms-blocked","status":"publish","type":"docs","link":"https:\/\/www.smsgatewaycenter.com\/blog\/kb\/what-is-cta-whitelisting-and-why-was-my-sms-blocked\/","title":{"rendered":"What is CTA whitelisting, and why was my SMS blocked?"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">If your SMS contains a link, an app link or a phone number for customers to call, that link or number must be <strong>whitelisted<\/strong> on the DLT portal where your business is registered. Messages carrying anything that isn&#8217;t whitelisted are blocked by the telecom operators and never reach the customer.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">These links and numbers are called <strong>CTAs (calls to action)<\/strong>. There are four types:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>URLs<\/strong>: website links, including short links.<\/li>\n\n\n\n<li><strong>APKs<\/strong>: Android app download links.<\/li>\n\n\n\n<li><strong>OTT links<\/strong>: links that open apps or platforms, such as WhatsApp links.<\/li>\n\n\n\n<li><strong>Callback numbers<\/strong>: mobile, landline or toll-free numbers you ask customers to call.<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">Why this rule exists<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">TRAI issued the direction on 20 August 2024 to stop SMS being used to spread phishing links and malicious apps. Operators have blocked messages with non-whitelisted URLs, APKs and OTT links since 1 October 2024. The February 2025 amendment to TRAI&#8217;s commercial communication rules extended the same scrubbing to callback numbers.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">How to tell if this is your problem<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Your delivery report shows <strong>CTA Mismatch<\/strong> for the failed messages.<\/li>\n\n\n\n<li>Messages <em>without<\/em> a link or number go through, but messages with one fail.<\/li>\n\n\n\n<li>You recently changed a landing page, short-link domain, app link or support number.<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">What to do<\/h2>\n\n\n\n<ol class=\"wp-block-list\">\n<li>Whitelist every link domain and number you use on your DLT portal (see <em>How do I whitelist URLs, app links and callback numbers on my DLT portal?<\/em>).<\/li>\n\n\n\n<li>Make sure the template&#8217;s variables use the right tags, such as <code>{#url#}<\/code> for links and <code>{#cbn#}<\/code> for numbers.<\/li>\n\n\n\n<li>Resend only to the numbers that failed.<\/li>\n<\/ol>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Official source:<\/strong> <a href=\"https:\/\/www.pib.gov.in\/PressReleaseIframePage.aspx?PRID=2058943\" target=\"_blank\" rel=\"noopener nofollow\">TRAI press release on URL\/APK\/OTT whitelisting (PIB)<\/a>; <a href=\"https:\/\/www.trai.gov.in\/sites\/default\/files\/2025-02\/Regulation_12022025.pdf\" target=\"_blank\" rel=\"noopener nofollow\">TCCCPR (Second Amendment) Regulations, 12 Feb 2025<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>If your SMS contains a link, an app link or a phone number for customers to call, that link or number must be whitelisted on the DLT portal where your business is registered. Messages carrying anything that isn&#8217;t whitelisted are blocked by the telecom operators and never reach the customer. These links and numbers are [&hellip;]<\/p>\n","protected":false},"author":118,"featured_media":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"doc_category":[2270],"doc_tag":[],"class_list":["post-3021","docs","type-docs","status-publish","hentry","doc_category-cta-whitelisting"],"year_month":"2026-09","word_count":264,"total_views":"2","reactions":{"happy":"0","normal":"0","sad":"0"},"author_info":{"name":"admin","author_nicename":"admin","author_url":"https:\/\/www.smsgatewaycenter.com\/blog\/author\/admin\/"},"doc_category_info":[{"term_name":"CTA Whitelisting","term_url":"https:\/\/www.smsgatewaycenter.com\/blog\/kb-cat\/cta-whitelisting\/"}],"doc_tag_info":[],"_links":{"self":[{"href":"https:\/\/www.smsgatewaycenter.com\/blog\/wp-json\/wp\/v2\/docs\/3021","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.smsgatewaycenter.com\/blog\/wp-json\/wp\/v2\/docs"}],"about":[{"href":"https:\/\/www.smsgatewaycenter.com\/blog\/wp-json\/wp\/v2\/types\/docs"}],"author":[{"embeddable":true,"href":"https:\/\/www.smsgatewaycenter.com\/blog\/wp-json\/wp\/v2\/users\/118"}],"replies":[{"embeddable":true,"href":"https:\/\/www.smsgatewaycenter.com\/blog\/wp-json\/wp\/v2\/comments?post=3021"}],"version-history":[{"count":0,"href":"https:\/\/www.smsgatewaycenter.com\/blog\/wp-json\/wp\/v2\/docs\/3021\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.smsgatewaycenter.com\/blog\/wp-json\/wp\/v2\/media?parent=3021"}],"wp:term":[{"taxonomy":"doc_category","embeddable":true,"href":"https:\/\/www.smsgatewaycenter.com\/blog\/wp-json\/wp\/v2\/doc_category?post=3021"},{"taxonomy":"doc_tag","embeddable":true,"href":"https:\/\/www.smsgatewaycenter.com\/blog\/wp-json\/wp\/v2\/doc_tag?post=3021"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}