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SMS Marketing 💬

Head West Team
Updated July 25, 2023
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What’s the best SMS marketing platform for eCommerce companies?

Attentive vs Postscript vs SMS Bump vs Voyage vs Emotive vs Twilio vs Klaviyo SMS

Our pick:


Postscript is the up and comer in the SMS marketing world, and we think it is the best tool for most eCommerce companies. It was founded in 2018 by StackCommerce alumni Adam Turner and Alex Beller who took the company through YC in the Winter class of 2019. They have built a best-in-class SMS marketing tool that executes well every step of the way from SMS collection to segmented campaign sends.

Our Pick


Postscript is the best SMS marketing platform for most eCommerce businesses.

When do you need an SMS marketing platform?

For small brands, you likely don’t need an SMS platform. SMS or short message service is the industry term for texts. And while it might sound like a great idea to text your customers or potential customers, our recommendation is that brands focus on email until scaling to at least $20M in revenue. Some younger, Gen-Z focused brands are built almost entirely on SMS lists, but we think most brands should scale email first. Why? 

Unlike emails which are free to send, SMS requires a small fee (.01 cents) per text. This cost is a legacy of phone carriers who developed SMS prior to messaging apps and charge companies to send texts over their rails (apparently Twitter racked up $60M per year in charges to telcos from bots sending fake two-factor authentication texts.) While the per text fee is small, it adds up over thousands of sends.  

The average American checks their phone 96 times per day, and open rates for SMS messages are typically very high (95-100%) compared to ~30% for email. Despite these high open rates, brands we spoke with typically generated 1-3% of last non-direct click revenue from SMS and 20-25% from email. There are a couple of factors driving this. First, collection rates of phone numbers are significantly lower than email. The typical collection rate on an email popup is 7-8% whereas the typical collection rate on an SMS popup is 3%. Second, the number of sends per week is much higher for email. The typical eCommerce company can send up to 5 emails per week without seeing a material impact to unsubscribes, whereas it isn’t recommended to send more than 2 texts per week. Customers are used to seeing many emails in their inbox, however, texts are more personal and the threshold for spam is lower. 

For these reasons, we recommend focusing on email before adding SMS. However, once your email channel has scaled, we think SMS is a great next step.   

Why we like Postscript:

List Growth Tools

Step one in building a successful SMS marketing channel is to build your opt-in list, and Postscript provides the tools to do it. Don’t worry, if you’re switching from a competitor, importing an existing SMS list is easy (Postscript will also verify the list is compliant). Postscript offers desktop and mobile popups that can collect both email and SMS and are optimized for conversion. Their pre-built templates offer enough customization to feel on brand and don't require any custom coding. They also offer SMS collection options after checkout which we love. The opt-in rate on checkout collection is much higher (typically 20%) and the checkout page is often underutilized real estate in eCommerce.  

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Postscript has developed tools for hyper segmented SMS sends. Other companies are optimized for generic SMS campaigns to your entire list which won't convert as well and cost you additional money to send non-targeted messages. Postscript integrates well with Shopify and Klaviyo so you can pull in data from those apps to target your sends (e.g., customers who have spent over $100 that you have not sent a promotional email in the last month). You can also segment based on SMS activity (e.g., send only to those on your list who clicked on a text mentioning XYZ product).

Two-way Messaging

Postscript was built to support two-way text conversations. While the US is far behind Asia in conversational commerce, if Asia is the guide, then conversational commerce is going to be a growing channel and not just a buzzword. Postscript houses all of the SMS conversations within the Responses tab so you can see the text history and purchase history with every customer conversation.

Customer Support

Postscript customers almost unanimously mentioned their strong customer support. As the smaller challenger to Attentive, we think Postscript has focused on this area as a differentiator. Their team is extremely knowledgeable about all things SMS and customers (especially larger companies) can expect hands on customer support.

Regulatory Compliance

SMS marketing is much more highly regulated than email or paid marketing channels, and it's critical that your company doesn’t run afoul of these regulations. In 1991, Congress passed the "Telephone Consumer Protection Act" or TCPA to reduce the number of spam calls. The act also covers text messages and allows for statutory damages of up to $500 per violation and up to $1,500 per violation if it was willful or knowing. In 2018, Uber settled a TCPA lawsuit alleging they sent automated text messages to individuals without their consent for $20M. Yikes! This is why it's critical that Postscript is on top of all of the regulations and will ensure that your business is compliant. We spoke with multiple companies who were using other SMS vendors and only found out that they were not in compliance when they switched to Postscript, and Postscript reps identified compliance issues with their SMS programs (😬). 


Postscript has integrations with nearly all of our recommended tools. Link it to Shopify our recommended eCommerce platform, Gorgias our recommended Customer Support Platform, Klaviyo our recommended Email Marketing Platform, and Okendo our recommended Review Tool. Linking to Postscript can make all of these tools better. For example, you could send your Okendo review requests through Postscript to increase collection rates. 

What we don’t like about Postscript: 


Like many marketing platforms, Postscripts native reporting will over attribute sales to their channel. Many customers we spoke with used Google Analytics as their source of truth for attribution. Reporting in Postscript is more intuitive and better than other SMS platforms but has room for improvement especially around attribution.


Postscript’s focus area is the US and Canadian markets. For businesses with large international presences, you might want to consider alternatives for those markets or for the entire SMS platform.  

AB Testing

Postscript offers AB testing for SMS, but we would like to see this feature improve over time. Historically Postscript customers were unable to AB test campaign flows although Postscript has recently rolled out this feature. We would also like to see AB test reporting improvements.

Postscript pricing:

Postscript offers four pricing tiers. The free plan will cost $0.015 per SMS and $0.045 per MMS (texts with photos or video). More expensive monthly plans will lead to lower per SMS and MMS fees and come with more support. As always, whisper 'Head West' at checkout for a special discount.


Attentive – Founded in 2016, Attentive is the 800 pound Gorilla of SMS marketing platforms. They have a similar platform to PostScript but have worse reporting tools, their integrations though more numerous are less seamless than PostScripts (especially the Klaviyo integration), and adding shortcodes to SMS is not as easy. We’ve also heard that customers who use Attentive and were looking to switch to another SMS provider struggled to get their SMS list from the platform to bring to another  

Voyage – Voyage is smaller than both Attentive and Postscript and while it might be slightly cheaper it lags both in features and has fewer integrations

SMSBump (Yotpo) – Acquired by Yotpo in January of 2020, SMSBump is now Yotpo’s SMS offering. While there is a better Yotpo integration with SMSBump, pricing is higher and its usability trails Postscript  

Emotive – Emotive is a smaller competitor that's built around two-way conversations with customers. While we love two-way conversations, we like that our recommended tool can handle both two-way conversations and campaign type sends efficiently. Emotive also has fewer automations and integrations than our recommended tool Postscript

Twilio – Twilio is actually the company that PostScript uses behind-the-scenes. Twilio has large customers like Uber and Netflix, but we don’t recommend it for eCommerce companies. It is less tailored to the eCommerce use case and will require much more custom development resources than our recommended tool Postscript

Klaviyo SMS – Klaviyo is our recommended email marketing platform and has announced SMS as a strategic focus. While it’s nice in theory to manage email and SMS on a single platform, we don't recommend it. Klaviyo’s main focus is email, and SMS has historically been an afterthought, and Klaviyo’s SMS product has suffered as a result. Customer profiles are built off email addresses in Klaviyo and merging profiles is difficult with Klaviyo SMS, so if someone has signed up for your email list with multiple emails (e.g., work and personal) then you may end up sending duplicate texts to the same person. Segmenting and AB testing is also more difficult with Klaviyo SMS vs our recommended solution


What is SMS marketing software?

SMS marketing software is a type of digital tool or platform designed to facilitate and streamline the process of sending promotional and marketing messages to a large group of people via SMS (Short Message Service). SMS marketing is a form of mobile marketing, where businesses and organizations use text messages to reach their target audience and communicate various promotional content, alerts, offers, reminders, and other relevant information.

What is the best SMS software for eCommerce?

We recommend Postscript as the best SMS software for eCommerce. Postscript is the up and comer in the SMS marketing world (competing against the 800 lb. gorilla Attentive), and we think they have built a best-in-class SMS marketing tool. Their platform executes well every step of the way from list growth tools to segmented campaign sends all while ensuring that your business stays in compliance (very important for SMS marketing).

What does SMS stand for?

SMS stands for "Short Message Service." It is a text messaging service that allows users to send short text messages between mobile devices. The concept of SMS was introduced in the 1980s, and the idea was to provide a simple and efficient way for mobile phones to exchange short text messages. At that time, mobile networks were primarily designed for voice communication, and SMS was considered a supplemental service. SMS became increasingly popular in the 1990s, and its usage exploded with the widespread adoption of mobile phones. The 160-character limit was initially set to fit within the signaling protocols of the GSM (Global System for Mobile Communications) and to utilize spare bandwidth efficiently. Since then, SMS has become an integral part of mobile communication, allowing people to send short and quick messages to one another across different mobile networks and devices, making it a ubiquitous and widely used service in the world of telecommunications.

What does MMS stand for?

MMS stands for "Multimedia Messaging Service." It is a standard for sending multimedia content, such as pictures, videos, audio files, and contact cards, via mobile devices. MMS allows users to send and receive multimedia messages to and from other mobile phones or email addresses. Unlike SMS (Short Message Service), which is limited to text messages of up to 160 characters, MMS allows for much larger messages that can include various types of media.

What are the common features of SMS marketing software?

SMS marketing software comes with various features to help businesses efficiently manage and execute their SMS marketing campaigns. Here are some of the common features you can find in SMS marketing software:

Bulk Messaging: The ability to send a large number of SMS messages simultaneously to a predefined list of recipients, making it easy to reach a wide audience.
Contact Management: Tools for managing contact lists, organizing subscribers, and segmenting the audience based on various criteria, allowing for targeted messaging.
Automation: The capability to automate SMS sending based on triggers, events, or scheduling, which saves time and ensures timely delivery of messages.
Personalization: Customization options to include personalized information such as the recipient's name or other relevant details, making the messages more engaging and relevant.
Opt-in/Opt-out Management: Features to handle subscription preferences, allowing users to opt-in or opt-out of receiving SMS messages, ensuring compliance with regulations and respecting user preferences.
Reporting and Analytics: Tracking and analyzing the performance of SMS campaigns, including delivery rates, open rates, click-through rates, and more, to measure the effectiveness of the marketing efforts.
Two-Way Communication: Some advanced SMS marketing platforms enable two-way communication, allowing recipients to respond to messages, which can be useful for customer support or feedback collection.
Scheduled Messaging: The option to schedule SMS messages to be sent at specific times or dates, allowing for planned and strategic communication.
Integration with Other Platforms: Integration capabilities with other marketing tools, CRM systems, or databases, enabling seamless data synchronization and more effective marketing efforts.
Message Templates: The ability to create and store message templates for easy reuse, streamlining the process of creating and sending messages.
URL Shortening: Some SMS marketing software may include URL shortening capabilities, which helps conserve character space when including website links in messages.
Compliance and Consent Management: Tools to manage compliance with SMS marketing regulations and maintain records of user consent for receiving marketing messages.

What are the benefits of SMS marketing?

SMS marketing offers several benefits that make it a valuable and effective tool for businesses and organizations. Here are some of the key benefits of SMS marketing:

High Open and Read Rates: SMS messages have exceptionally high open and read rates, often exceeding 90%. Most recipients open and read SMS messages within minutes of receiving them, ensuring that your message gets noticed promptly.
Immediate Delivery: SMS messages are delivered instantly, making it an ideal channel for time-sensitive promotions, urgent notifications, and real-time communication with customers.
Direct and Personal Communication: SMS marketing enables direct and personal communication with customers. Messages are delivered to their mobile devices, which are typically within arm's reach, ensuring a high level of engagement.
Short and Concise Messaging: The character limit of SMS messages (usually 160 characters) forces marketers to be concise and get to the point quickly, resulting in clear and focused communication.
Higher Engagement and Conversion Rates: Due to the immediacy and personal nature of SMS, it often leads to higher engagement and conversion rates compared to other marketing channels.
Opt-in Audience: SMS marketing requires recipients to opt-in to receive messages, ensuring that you are reaching a willing audience interested in your products or services.
Mobile Device Reach: With the increasing use of smartphones, SMS marketing allows you to reach customers on a device they carry with them all the time, increasing the likelihood of immediate attention.
Cost-Effectiveness: SMS marketing can be a cost-effective marketing strategy, especially when compared to traditional advertising methods like print or TV.
Easy Implementation and Integration: SMS marketing is relatively easy to implement, and most businesses can integrate it into their existing marketing strategies with minimal effort.
Automated and Scheduled Messaging: Many SMS marketing platforms offer automation and scheduling features, allowing you to send messages at optimal times or set up automated campaigns.
Higher Response and Interaction Rates: SMS marketing often results in higher response rates compared to other communication channels, making it suitable for conducting surveys, collecting feedback, or running interactive campaigns.
Trackable and Measurable Results: Most SMS marketing platforms provide analytics and tracking tools, allowing you to measure the performance of your campaigns and make data-driven improvements.
Complementing Other Marketing Channels: SMS marketing can complement other marketing channels, enhancing overall marketing efforts and creating a more comprehensive customer communication strategy. However, it's important to note that while SMS marketing has numerous benefits, it should be used responsibly and in compliance with relevant regulations to avoid spamming recipients and maintain a positive brand image.

Is SMS marketing illegal?

No, SMS marketing is not inherently illegal. However, it is subject to various laws and regulations to protect consumers from unsolicited and spammy messages. To conduct SMS marketing legally, businesses and organizations must comply with these regulations, which may vary depending on the country or region where the messages are being sent.

Some common regulations that govern SMS marketing include:
Obtaining Consent: In most countries, businesses are required to obtain explicit consent from recipients before sending them SMS marketing messages. This consent must be informed and specific, meaning that the recipients must be aware of what type of messages they are signing up for and must agree to receive them.
Providing Opt-out Options: Recipients must have a clear and straightforward way to opt-out or unsubscribe from receiving SMS marketing messages. Businesses must honor these opt-out requests promptly and avoid sending further messages to opted-out individuals.
Identifying the Sender: SMS marketing messages must clearly identify the sender or the business on whose behalf the message is being sent.
Compliance with Do-Not-Call Lists: In some regions, there are national or regional do-not-call lists, and businesses must ensure they do not send SMS marketing messages to numbers listed on these registers.
Content Compliance: The content of SMS marketing messages should comply with applicable laws and should not include misleading information or deceptive practices.
Restrictions on Sensitive Topics: Some jurisdictions may impose additional restrictions on SMS marketing messages related to certain topics like healthcare, finance, or adult content.

How do I choose an SMS marketing platform?

Choosing the right SMS marketing platform is crucial for the success of your SMS marketing campaigns.
Here are some key factors to consider when selecting an SMS marketing platform:
Features and Functionality: Assess the platform's features and functionality. Look for essential capabilities such as bulk messaging, contact management, automation, personalization options, and reporting/analytics. Consider whether the platform meets your specific business needs and campaign requirements.
Ease of Use: Choose a user-friendly platform that is easy to navigate and understand. A simple and intuitive interface will save you time and reduce the learning curve for your team.
Integration: Check if the platform integrates smoothly with your existing systems, such as CRM software, marketing tools, or e-commerce platforms. Seamless integration can streamline data management and enhance the effectiveness of your marketing efforts.
Message Delivery and Reliability: Ensure that the platform has a robust and reliable message delivery system. Messages should be delivered promptly and consistently to reach your target audience effectively.
Compliance and Consent Management: Verify that the platform provides tools for managing compliance with SMS marketing regulations, including obtaining proper consent from recipients and handling opt-out requests.
Pricing and Scalability: Evaluate the pricing plans offered by the platform and consider whether they align with your budget and business requirements. Also, check if the platform is scalable to accommodate the growth of your SMS marketing campaigns.
Customer Support: Look for a provider that offers reliable customer support. Responsive support can be critical in resolving issues quickly and getting the most out of the platform's features.
Security and Privacy: Ensure that the platform follows industry best practices for security and data privacy. You'll be dealing with sensitive customer information, so data security is paramount.
Delivery Tracking and Analytics: The platform should provide comprehensive reporting and analytics features to track the performance of your SMS campaigns. This will help you measure the effectiveness of your marketing efforts and make data-driven decisions.
Reviews and Reputation: Research the platform's reputation and read reviews from other users. Look for feedback on user experience, reliability, customer support, and overall satisfaction.
Trial Period or Demo: If possible, take advantage of a trial period or request a demo to test the platform's features and see if it meets your expectations.
Local Compliance and Reach: If you plan to target specific regions or countries, consider whether the platform complies with local regulations and supports international SMS messaging. By carefully evaluating these factors and understanding your specific SMS marketing needs, you can make an informed decision when choosing an SMS marketing platform that aligns with your business goals and objectives.

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