Two-way SMS API for interactive conversations

Build engaging, two-way SMS conversations directly in your applications. Automate replies, collect feedback, and provide real-time support — all through a single API.

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Already 18,081 clients trust us for two-way customer interactions

Why choose BulkGate for your two-way SMS API

Two-way SMS API webhooks diagram for real-time incoming messages

Unified API with real-time webhooks

Manage outgoing and incoming SMS through one API. We deliver replies to your system instantly via webhooks.

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Powerful automation toolkit

Automate conversations with workflows, keyword analysis, SMS chatbots, and automatic replies.

Global SMS reach – two-way conversations in 125 countries worldwide

Global reach with local numbers

Enable two-way conversations in 125 countries. Manage Short Codes and System Numbers through one API.

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What you can build with our two-way SMS API

Our flexible two-way API lets you create powerful, automated, and interactive communication workflows.

Automated support

Bookings

Data & leads

/* After setting up a webhook you will be able to receive customers replies. */ { "status":"10", "from":"420777777777", "text":"How does data structure captured via webhook looks like?" }

Automate customer support and FAQ

Automatically recognize keywords and answer common questions without burdening your support team.

/* Webhook captures status 10 and using parameter text you can decide whether to confirm / modify / cancel the reservation. */ { "status":"10", "from":"420777777777", "text":"#YES" }

Build interactive appointment management

Let customers confirm, reschedule, or cancel appointments with a simple SMS reply and automate the entire booking cycle.

/* Use webhooks to create autommated data collection and leads */ { "status":"10", "from":"420777777777", "text":"example@gmail.com" }

Automate data collection and lead generation

Engage prospects with automated questions and collect emails, preferences, or survey responses directly via SMS.

Key features of the two-way SMS API

Keyword analysis and automated actions Analyze keywords and automatically trigger workflows, chatbots, or replies, including STOP processing.

Full Unicode support Process replies in any language, including diacritics, special characters, and emoji.

Multiple number types via API Manage short codes and system numbers via API by country and use case.

Conversation thread management Manage conversations using thread IDs in your application or CRM.

Dynamic personalization in replies Personalize replies with names, order details, and other data, including natural grammatical inflection.

Robust API protection and full budget control

Secure your two-way SMS API against misuse and unexpected costs. Our platform gives you the tools to protect your integrations and manage spending with confidence.

Two-way SMS API budget management interface for sending limits

Granular access management Manage projects and clients with separate API keys, each with its own permissions and limits.

SMS API budget management interface for sending cost limits

Always within budget Set daily, monthly, or country-specific limits and get alerts before exceeding your budget.

SMS API anti-fraud protection graph monitoring sending patterns

Automatic abuse protection Protect your account with sending limits, duplicate detection, and real-time monitoring of suspicious activity.

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Flexible integration options

Integrate our two-way SMS API seamlessly into your applications and workflows.

Clean REST API

Send and receive SMS messages and handle replies via webhooks using our clean and stable REST API.

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Ready-to-use SDKs

Speed up integration with the official PHP SDK. It greatly simplifies both sending messages and processing inbound webhook data.

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Email-to-SMS

Forward SMS replies to email and respond back instantly — no coding required.

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Start your first two-way conversation in minutes

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Generate your unique API key in the portal

Send your first message and receive a reply using our quickstart guide

Frequently asked questions

How do I receive inbound SMS via API?

Set up a webhook URL in your BulkGate account. Whenever a reply or new message arrives at your number, our platform instantly sends an HTTP POST request with message data (sender, text, etc.) to your webhook URL. Your application then processes the data and can trigger an automated response.

What Sender ID do I need for two-way SMS API?

To receive replies via API, you need a reply-capable number such as a System Number or Short Code. Standard text Sender IDs (e.g., "MyBrand") cannot receive replies and won't work for two-way SMS. While you can use your Own Number, replies will go directly to your phone, not to the API.

Can I automate replies to inbound SMS?

Yes — that's the core strength of the API. Your webhook script can analyze the text of each inbound message and instantly trigger an API call to send a customized, automated response.

Is there any delay in receiving SMS replies?

No. Replies are processed by our SMS gateway and delivered to your webhook in near real-time, typically within seconds. This enables smooth, conversational experiences.

How do I manage multiple concurrent conversations?

Each inbound message includes the sender's phone number, which you can use as a unique identifier to manage separate conversation states in your application or database. We also provide message and conversation IDs to help you correctly merge interactions into threads.

Are inbound SMS messages free?

Yes, receiving SMS messages via webhooks is completely free. You only pay for outgoing messages you choose to send.

Ready for real conversations?

Customer communication is not a monologue. Join 18,081 businesses that build better customer relationships with two-way SMS.

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