Is SMS marketing legal, and what are the rules?

Yes, but it's tightly regulated. In the US, the TCPA requires prior express written consent before sending marketing texts, a clear opt-out (reply STOP), and honoring quiet hours. Carriers also enforce their own rules via 10DLC registration. Reputable platforms build opt-in capture and opt-out handling in - use them, and never text purchased lists.

SMS or WhatsApp - which should I use?

It depends on your audience's geography. SMS dominates in the US and Canada, while WhatsApp is the default in much of Europe, Latin America, the Middle East, and Asia. If your customers are international, a WhatsApp-first tool (Wati) or an omnichannel platform (respond.io) makes sense; for US e-commerce, SMS-first (Postscript) usually wins.

How much does SMS marketing cost?

Most platforms charge a monthly plan plus per-message or per-contact fees, and carrier or WhatsApp API charges are often passed through on top. Costs scale with list size and send volume, so estimate messages per month. Also budget for 10DLC registration fees in the US, which carriers require for business texting.

What's the difference between broadcast SMS and chat automation?

Broadcast SMS sends one message to many contacts - promotions, drops, announcements. Chat automation (chatbots and flows) handles one-to-one conversations automatically, like answering FAQs, qualifying leads, or recovering carts. Manychat leans automation; Postscript and SimpleTexting lean campaigns; many businesses use both.

Best SMS & Chat Marketing Software (2026)

SMS and chat marketing software lets you reach customers where they actually read messages - text, WhatsApp, Instagram DMs, and website chat - with open rates that dwarf email. For e-commerce and local businesses, it's one of the highest-ROI channels for promotions, abandoned-cart recovery, and fast two-way support.

The category covers a few distinct jobs: broadcast SMS campaigns, conversational chat automation (chatbots and flows), WhatsApp Business messaging, and shared-inbox texting for sales and support. Some tools specialize in one channel; others unify several. Pick based on where your customers are and whether you need one-to-many campaigns or one-to-one conversations.

Pricing is usually a monthly plan plus per-message or per-contact costs, and carrier/WhatsApp fees are often passed through on top. Compliance matters more here than in email: you need explicit opt-in and easy opt-out. The picks below span e-commerce SMS, WhatsApp, chat automation, and business texting.

Our top SMS & Chat Marketing picks

Who each pick is actually for

Two facts below, both arithmetic rather than opinion, taken from the review scores in our catalog. Neither is a recommendation, and a high score from a small group of users is a different claim from a high score at scale, so the sample size is shown alongside every figure.

Most reviewed

SimpleTexting

4.6 across 450 reviews

Note the size of that sample, because it is the largest in the category. Nothing here clears 500 reviews, so treat every rating on this page as directional rather than settled: a tenth of a point between two tools is noise. SimpleTexting earns the top count by being the general-purpose option, campaigns and two-way messaging without tying you to one storefront or one channel, which is also why the specialists below beat it at their own jobs.

Highest rated

Postscript

4.8 across 400 reviews

Built around Shopify, and the score reflects that fit: a narrow tool rated by exactly the people it was designed for, not a general verdict on SMS platforms. If you are not on Shopify, this number tells you nothing you can use. It starts free, which in this category never means cheap, because carrier registration and per-message fees ride on top of whatever the platform charges.

None of that decides it for you

You are about to send your first campaign in the US: SimpleTexting - The gentlest on-ramp in the family at $39, with keyword opt-ins, STOP handling, and campaign sending that does not need a specialist. Two things nobody puts on a pricing page: US marketing texts need documented written consent collected before the first send, and carriers charge separately to register your campaign and again per message, so the plan price is not the bill.
Your customers are outside North America: Wati - WhatsApp Business API from $59, with broadcasts, templates, and a shared inbox for the channel most of the world actually replies on. An SMS-first platform is simply the wrong shape for a market where nobody texts a business.
The conversation starts in an Instagram comment: Manychat - Free to start, and the only thing here built around DM automation: comment triggers, keyword replies, and a clean handoff to a human. If your audience follows you rather than subscribes to you, that DM thread is your list.
The messages will contain something a patient told you: Textline - HIPAA-compatible messaging is what you are buying here: controlled access, audit trails, and a compliance posture you can point someone at. The cheaper tools here quietly assume every message you send is marketing copy. Textline stopped publishing plan prices, so every tier is now a sales conversation, which is worth knowing before you start one.
Reps text prospects from inside HubSpot or Salesforce: Salesmsg - $25 for two-way texting that lands on the CRM record, so the next person to open the deal can see what was already said. If calling is the main motion rather than texting, you are really shopping for a dialer, and that comparison sits in our business phone guide instead.
You sell online but not on Shopify: Sender - Email and SMS against one subscriber list with cart and promo automation, starting free, which is the cheapest way to run both channels off the same record. Postscript is the better version of this and is not available to you.
You want the bot to qualify people before a human replies: Landbot - Free to start, and built as a conversation designer rather than a broadcast tool: branching, rules, and handoff across WhatsApp and your website. A campaign platform sends to a list; this one runs the exchange that follows.

What to look for

The channel your customers use - SMS, WhatsApp, Instagram/Facebook, or web chat. Buy for where your audience actually is.
Campaigns vs. conversations - some tools excel at one-to-many broadcasts, others at one-to-one automated chat or shared-inbox texting. Know which you need.
Compliance built in - explicit opt-in capture, easy opt-out (STOP), and quiet-hours controls keep you on the right side of TCPA and carrier rules.
Total messaging cost - watch for per-message fees, per-contact pricing, and pass-through carrier or WhatsApp API charges on top of the base plan.
Integrations - native Shopify, CRM, and e-commerce connections power automations like abandoned-cart and post-purchase flows.

Frequently asked questions

Is SMS marketing legal, and what are the rules?: Yes, but it's tightly regulated. In the US, the TCPA requires prior express written consent before sending marketing texts, a clear opt-out (reply STOP), and honoring quiet hours. Carriers also enforce their own rules via 10DLC registration. Reputable platforms build opt-in capture and opt-out handling in - use them, and never text purchased lists.
SMS or WhatsApp - which should I use?: It depends on your audience's geography. SMS dominates in the US and Canada, while WhatsApp is the default in much of Europe, Latin America, the Middle East, and Asia. If your customers are international, a WhatsApp-first tool (Wati) or an omnichannel platform (respond.io) makes sense; for US e-commerce, SMS-first (Postscript) usually wins.
How much does SMS marketing cost?: Most platforms charge a monthly plan plus per-message or per-contact fees, and carrier or WhatsApp API charges are often passed through on top. Costs scale with list size and send volume, so estimate messages per month. Also budget for 10DLC registration fees in the US, which carriers require for business texting.
What's the difference between broadcast SMS and chat automation?: Broadcast SMS sends one message to many contacts - promotions, drops, announcements. Chat automation (chatbots and flows) handles one-to-one conversations automatically, like answering FAQs, qualifying leads, or recovering carts. Manychat leans automation; Postscript and SimpleTexting lean campaigns; many businesses use both.