Free and open first

Best Transactional SMS Software in 2026

Transactional SMS software is for sending messages tied to events such as account activity or service updates. Compared on delivery status, two-way messaging, webhooks, and SMS API support, the entries can be assessed against your messaging workflow. Monthly message limits and pay-as-you-go availability help compare usage options; free-plan details and paid-from pricing add cost context. ClickSend SMS API and Mailchimp are among the named options, alongside Bandwidth Messaging API and Telnyx SMS API. Consider the volume and interaction your messages require when weighing these listed features.

76 apps
Research read 23 Sept 2026
How the order is worked out

1

Alibaba Cloud Short Message Service

Free plan AndroidAPIiPhone+1

7.7 Visit site
2

BulkGate

Free plan AndroidAPIWeb

BulkGate offers multiple ways to connect and tools for both outbound and two-way messaging. Check destination-specific rates, and note the phone and sleep-mode limits if using Android Mobile Connect.

7.4 From €0.05 Visit site
3

LINK Mobility SMS API

Free plan AndroidAPIiPhone+1

LINK Mobility SMS API provides programmable, two-way messaging with delivery reports and webhooks. Its freemium and pay-as-you-go models suit web-based systems that need embedded SMS communication.

7.4 Visit site
4

Mailchimp
by Mailchimp
Free plan AndroidAPIiPhone+1

Choose Mailchimp if you want email marketing with automation, segmentation and campaign testing in one service.

7.4 Free plan · 14-day trial Visit site
5

Clickatell SMS API

Free plan APIWeb

Clickatell combines SMS APIs with web tools, two-way messaging, and a free testing sandbox. Review destination- and message-specific costs before using its pay-as-you-go option.

7.2 Pricing on request Visit site
6

QuickAuth Transactional SMS API

Free plan AndroidAPIiPhone+1

QuickAuth combines OTP delivery, business messaging, campaign tools, and fraud controls in one API.

7.2 Pricing on request Visit site
7

Sinch Verification API

Free plan AndroidAPIiPhone+1

Sinch Verification API offers several phone-based verification methods and developer access through REST and mobile SDKs.

7.2 Visit site
8

Gupshup
by Gupshup
Free plan APIWeb

Gupshup combines conversational agents, campaign tools, channel support, and human escalation.

7.1 From $0.00 Visit site
9

Infobip SMS API
by Infobip SMS API
Free plan APIWeb

Infobip SMS API covers sending, receiving, and delivery reporting, with developer libraries and business integrations.

7.1 60-day trial Visit site
10

MessageFlow SMS API

Free plan APIWeb

MessageFlow combines SMS campaign and API capabilities with delivery monitoring, abuse protection, and consent controls.

7.0 30-day trial Visit site
11

Messente
by Messente
Free plan APIWeb

Messente combines messaging channels with OTP and number-lookup services, plus API and integration options.

7.0 Pricing on request Visit site
12

Plivo Verify

Free plan APIWeb

Choose Plivo Verify if your direct brand needs configurable OTP delivery and Fraud Shield, and can meet the monthly commitment.

6.9 Visit site
13

Sendozi Transactional SMS

Free plan APIWeb

Sendozi combines transactional SMS, bulk campaigns, personalization, scheduling, and delivery reporting for Nigerian numbers.

6.9 From 7 NGN Visit site
14

seven SMS Gateway API

Free plan APIWeb

seven SMS Gateway API combines automated two-way messaging, bulk delivery, reporting, and several developer interfaces.

6.9 Visit site
15

SMSala
by SMSala
Free plan APIWeb

SMSala combines messaging, verification, and other communications APIs, with delivery reporting and developer resources.

6.8 Pricing on request Visit site
16

SMSGlobal API

Free plan APIWeb

SMSGlobal API provides application-level SMS sending with scheduling, receipts, and several sender options. Note its one-way description and AEDT scheduling requirement when planning an integration.

6.8 Visit site
17

SMSPortal

Free plan APIWeb

Choose SMSPortal if your business needs SMS or WhatsApp messaging, inbound replies, API access or automated journeys.

6.8 Free plan · paid from $0.08 Visit site
18

2Factor.in OTP API

Free plan Web

Choose 2Factor.in OTP API if a web based OTP service with a free sandbox, REST API, and SDKs fits your evaluation or implementation needs.

6.7 Free plan · paid from ₹4,999/mo Visit site
19

Textbelt

Free plan APISelf-hosted

Textbelt provides SMS sending, OTP verification, and a self-hosted option, with one free daily text and one-time paid credits.

6.7 Free plan Visit site
20

BulkSMS.com

Free trial APIiPhoneMac+2

BulkSMS.com offers web, desktop, and developer routes for international SMS campaigns. Pay-as-you-go credits have no contracts, but delivery and compliance conditions differ by destination.

6.5 Visit site
21

Callr

Free trial AndroidAPIiPhone+1

Callr combines programmable communications, tracking, conversation intelligence, and AI agents for business workflows.

6.5 From €599/mo Visit site
22

ClickSend SMS API

Free trial AndroidAPIExtension+3

ClickSend combines business SMS, two-way replies, API tools, and integrations for recurring workflows. It has a 14-day trial but no free plan, and carrier fees and message-part charges can apply.

6.4 14-day trial Visit site
23

Africa's Talking SMS

Free plan Web

6.2 Free plan Visit site
24

CM.com Business Messaging API

Free trial APIWeb

CM.com provides a broad messaging API with fallback routing, rich content, analytics, and developer tooling.

6.1 Free plan · paid from €315/mo Visit site
25

Conexteo

Free trial APIWeb

Conexteo combines campaign management, programmable messaging, automation, and agency controls across SMS and RCS.

6.1 Pricing on request Visit site

#1Places #1, #2, #3, #4, #5 on this list can be bought by the makers of the software on it. See the price

More in Marketing