ClientWindow WhatsApp API

Connect with clients where they’re most responsive, using our compliant WhatsApp messaging gateway.

Build powerful, automated WhatsApp messaging into your platform for reminders, document requests, status updates, and real-time interactions.
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Why WhatsApp?

  1. 2.7 billion users globally
  2. 98% message open rate
  3. 5x faster client response vs. email
  4. Increasingly demanded by clients in financial services, accountancy and other regulated industries

What can you do with the ClientWindow API?

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Two-Way WhatsApp Communication

Capture responses, confirmations, and client feedback instantly
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Send Files

Deliver payslips, contracts, onboarding docs via secure WhatsApp messages
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Trigger Notifications

Automate KYC requests, deadline reminders, and event updates
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Secure & Auditable

Encrypted messaging with full communication history retention
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Flexible Integration

REST API with rich metadata, delivery receipts, and webhook support

What can you do with the ClientWindow API?

icon of settings cog

Two-Way WhatsApp Communication

Capture responses, client instructions and feedback securely
iconc of files in a folder

Send Files

Deliver payslips, contracts, onboarding docs via secure WhatsApp messages
icon of notification bell

Trigger Notifications

Automate KYC requests, deadline reminders and account updates
icon of speech bubble and a shield

Secure & Auditable

Encrypted messaging with full communication history retention
icon of settings cog

Flexible Integration

REST API with rich metadata, delivery receipts, and webhook support

Who it's for

Accountancy & Payroll Vendors
Chase information, Distribute Payslips and Manage salary queries
Payments & Wealth Platforms
Accept instructions, Notify clients of payments, Manage compliance actions
Education Platforms
Engage with Parents and Students securely, Share timetable, updates and event information
Legal Software
KYC and Onboarding, Case Updates & Document Sharing
Crew & HR Management
Deliver payslips, roster updates, onboarding forms, training reminders

Who it's for

Accountancy & Payroll Vendors
Chase information, Distribute payslips
Payments & Wealth Platforms
Notify clients of payments, compliance actions
Education Platforms
Engage students and parents securely
Real Estate & LegalTech
Share viewing info, contracts, or legal instructions
Crew & HR Management
Deliver payslips, roster updates, onboarding forms, training reminders

Enterprise-Grade Security

  1. End-to-end WhatsApp Encryption
  2. ISO 27001 certified infrastructure
  3. GDPR-compliant data handling
  4. Role-based API key access
  5. Full audit trails of all messaging activity

Built for Developers

  1. Easy-to-use REST API with supporting documentation
  2. Fast onboarding and integration support
  3. WhatsApp Templates, Delivery and Read Statuses, Opt-In Management
  4. Webhook events for real-time workflows

Pricing

  1. Simple monthly access fee
  2. Usage-based message billing
  3. Optional add-ons: file hosting, message archiving, dedicated support
Talk to our team

Pricing

  1. Simple monthly access fee
  2. Usage-based message billing
  3. Optional add-ons: file hosting, message archiving, dedicated support
Talk to our team