What is SMS?
SMS (Short Message Service) is the standard text messaging technology built into virtually every mobile phone. It requires no internet connection, no app installation, and no account. It works natively on any mobile device through your carrier. Because of this, SMS messages are delivered almost instantly and reach customers wherever they are.
SMS vs. MMS
SMS is limited to plain text. Each SMS is made up of one or more segments: each segment supports up to 160 characters (or 70 characters if special characters are used), and a single message can contain multiple segments.
MMS (Multimedia Messaging Service) extends this significantly, supporting up to 1,600 characters plus images or GIFs in a single message. Both formats are widely supported across carriers and devices. SMS is ideal for concise, action-driven messages, while MMS is well suited for product showcases and visually rich promotions.
How SMS compares to other messaging channels
SMS is often compared to other communication channels, but it stands apart in a few key ways:
Channel | Key difference | Why SMS is better |
Requires an internet connection and is prone to spam filters and crowded inboxes. | SMS is delivered directly to the recipient's native messaging app and has an average open rate of around 98% versus roughly 20-25% for email, and most texts are read within minutes. There is no spam folder, no inbox competition, and no algorithm deciding whether your message gets seen. | |
App-based messaging (WhatsApp, iMessage, Facebook Messenger, etc.) | These platforms are tied to specific ecosystems. Both the sender and recipient need accounts on the same platform, and messages are only delivered if the recipient has the app installed and active on their device. | SMS works universally across all carriers and devices with no accounts, no apps, and no ecosystem dependency. You can reach any mobile subscriber regardless of what apps they use or what device they own. |
RCS (Rich Communication Services) | RCS is the next-generation successor to SMS, offering richer features like read receipts, high-resolution media, and interactive buttons. However, it requires both device and carrier support and is not yet universally available. | SMS reaches 100% of mobile devices today. RCS is promising but still dependent on carrier rollout and device compatibility. For broad, reliable reach, SMS remains the safer choice (for now). |
Why use SMS for marketing?
SMS is one of the most effective marketing channels available. Here is why brands are making it a core part of their strategy:
SMS messages have an average open rate of around 98%, compared to roughly 20-25% for email. The vast majority of texts are read within the first few minutes of being received.
Text messages feel more immediate and personal than email, making them ideal for time-sensitive promotions, cart recovery, and customer re-engagement.
Unlike email, SMS lands directly in the native messaging app with far less noise and no algorithmic filtering standing in the way.
Because SMS reaches customers where they already are, it consistently drives strong click-through and conversion rates for e-commerce brands.
How does it work?
SMS marketing works by sending text messages to a list of subscribers who have opted in to receive communications from your brand. Messages are sent and received through a dedicated phone number assigned to your business.
Toll-Free Numbers (TFNs)
A Toll-Free Number (TFN) is a 10-digit number with a toll-free prefix used to send and receive SMS and MMS messages at scale. TFNs are the standard number type for e-commerce SMS marketing due to their high throughput, broad carrier support, and ability to handle both SMS and MMS.
When you subscribe to a TxtCart plan, a US and/or Canadian TFN is automatically requested and provisioned for your store. You do not need to source or configure a number yourself. Once your number is approved and verified, you are ready to start sending.
If you want to reach subscribers in additional regions beyond the US and Canada, you can purchase additional TFNs for those regions directly through TxtCart. Each TFN enables TxtCart to send messages to subscribers in its corresponding region.
Number types
Different number types are available for SMS marketing, each with its own capabilities, use cases, and availability on TxtCart:
Number type | Best for | TxtCart support |
Toll-Free Number (TFN): Default | E-commerce brands sending marketing messages at scale. High throughput, supports SMS and MMS, and works well for both campaigns and automated flows. | Automatically provisioned for the US and Canada when you subscribe to a TxtCart plan. Recommended for most stores. |
10DLC (10-Digit Long Code): Supported | Brands that prefer a standard local-looking phone number for conversational or lower-volume messaging. Requires an additional carrier registration and verification before it can be used. | Very large stores that send more than 200,000 messages a day, or that need a local area number. |
Short Code: Not supported | High-volume senders who need maximum throughput. Short codes are 5-6 digit numbers that are highly recognizable but require a lengthy approval process and significant cost. | Not currently supported on TxtCart. |
RCS (Rich Communication Services): Coming soon | Brands that want to send rich, interactive messages with images, buttons, and read receipts, similar to a native app experience delivered through the messaging app. | Not yet supported, but planned for the near future. |
SMS compliance and regulations
SMS marketing is subject to strict regulations, and compliance is not optional. Before a TFN can be approved and used to send marketing messages, it must meet specific requirements set by carriers and regulatory bodies. Failure to comply can result in your number being flagged, messages being blocked, or your account being suspended.
Every region has its own regulatory framework. In the United States, this is primarily governed by the TCPA (Telephone Consumer Protection Act) and CTIA guidelines. In Canada, CASL (Canada's Anti-Spam Legislation) sets the rules. Regardless of region, the core principle is the same: you can only send marketing messages to people who have explicitly agreed to receive them.
Customers vs. subscribers
An important distinction to understand is the difference between a customer and a subscriber.
A customer is someone who has made a purchase or interacted with your store.
A subscriber is someone who has explicitly opted in to receive SMS marketing messages from your brand. These are not the same thing. Just because someone bought from you does not mean they have consented to receive promotional texts. In order to send someone a marketing SMS, they must first opt in (either through a pop-up, or during checkout).
⚠️Texting someone who has not explicitly opted in to receive SMS marketing from your brand is a compliance violation and can result in carrier filtering or legal liability.
Transactional vs. promotional messaging
Not all SMS messages are treated the same under compliance rules. There are two main categories:
Transactional messages are triggered by a specific customer action and relate directly to a transaction (such as order confirmations, shipping updates or support messages). These are generally held to a lower compliance bar because the customer expects them as part of their purchase.
Promotional messages are marketing-driven and intended to drive purchases or engagement (such as sales announcements, discount codes, or campaign blasts). These require explicit written opt-in consent and must include a clear opt-out mechanism (typically a STOP keyword).
TxtCart's flows and campaigns are designed with compliance in mind, including opt-out handling, Quiet Hours enforcement, and proper consent tracking.
Supported regions
Each country or region requires its own dedicated phone number for SMS marketing.
This is both a technical and a compliance requirement. Carriers and regulatory bodies in each region have their own rules governing how businesses can send marketing messages, what disclosures must be made, how opt-ins are collected, and how opt-outs must be handled.
Sending messages across regions using a single number can lead to poor deliverability, carrier filtering, or regulatory violations, which is why we only supported dedicated TFNs for each individual region.
Currently supported regions
TxtCart currently supports SMS marketing in the following regions:
Region | How to get started |
United States (US) | Automatically provisioned when you subscribe to a TxtCart plan. |
Canada (CA) | Automatically provisioned alongside your US number. |
Australia (AU) | Available for purchase directly from your Messaging Settings inside TxtCart. |
United Kingdom (UK) | Requires a legally registered business and supporting documentation. To acquire a UK TFN, contact our support team via live chat. |
Regions coming in 2026
TxtCart has plans to support more than 35 additional regions in 2026, including:
Region | Region | Region |
Netherlands | France | Germany |
United Arab Emirates | New Zealand | Mexico |
Spain | Belgium | Singapore |
Sweden | Finland | South Africa |
Israel | Italy | Philippines |
Poland | Ireland | India |
Switzerland | Norway | Puerto Rico |
Austria | Denmark | Japan |
Chile | Colombia | Hungary |
Indonesia | Malaysia | Nigeria |
Portugal | Brazil | Peru |
Russia | South Korea | Ukraine |
How TxtCart can help your SMS marketing
TxtCart is built specifically for Shopify merchants and gives you everything you need to run a successful SMS marketing program. From automated messaging to manual campaigns and subscriber growth tools, TxtCart handles the complexity so you can focus on growing your store.
Flows
Flows are fully configurable automations that allow you to target specific subscribers dynamically based on their behaviour or actions taken within your store. Whether it is an abandoned cart, a post-purchase follow-up, or a browse abandonment trigger, flows run in the background 24/7, recovering revenue and driving engagement without any manual effort on your part.
Campaigns
Campaigns are one-time broadcast messages sent to a full audience within your subscriber list (or to your entire subscriber list). They are ideal for promotions, product launches, seasonal sales, and any other time you want to reach your audience with a targeted message. You can schedule campaigns in advance or send them immediately.
Growing a subscriber list
Your subscriber list is the foundation of your SMS marketing program. TxtCart provides the tools to help you grow it compliantly and effectively by integrating with your Shopify to capture subscribers at checkout.
Every opt-in is automatically added to your subscriber list, tracked and documented to keep your program compliant.
This allows you to gradually grow an SMS audience that is fully compliant with regulations.
💡Tip:
Still have questions?
Please feel free to reach out to our wonderful Support team at support@txtcartapp.com or via Live Chat.