Glo Invoice's API and webhook system let you wire invoice, payment, and customer events into any tool in the Zapier ecosystem. Push new paid invoices into Google Sheets, post Sent → Paid status to Slack, create a Notion page when a new customer signs an estimate, or trigger a Mailchimp campaign the moment an invoice is overdue. If a workflow can be described in plain English, you can build it without code.
How the workflow works
Create an API key
From Admin → API Keys, generate a Glo Invoice API key. Copy it — Zapier will ask for it once.
Set up a webhook
From Admin → Webhooks, point a webhook at your Zapier 'Webhooks by Zapier' trigger URL for the events you care about.
Build your Zap
Map invoice or payment fields into the Zapier action — Google Sheets row, Slack message, Notion page, Mailchimp contact, whatever.
Let it run
Every matching event in Glo Invoice fires the Zap. Edit, pause, or branch the workflow from Zapier any time.
Real use cases
Paid invoices into Google Sheets
Every Paid invoice appends a row to a revenue tracking sheet with customer, total, date, and payment method.
Slack alerts for big payments
Post a celebration message to #wins the moment an invoice over $5,000 is marked Paid.
Notion CRM sync
Create a Notion page for every new customer, including contact info, first job total, and signed estimate link.
Overdue follow-up campaigns
When an invoice goes overdue, add the customer to a Mailchimp drip campaign — automatic recovery without lifting a finger.
What you get
- REST API with bearer-token auth
- Webhooks for invoice, payment, customer, estimate events
- Per-team API keys with revocation
- Webhook retry and delivery logs
- Works with Zapier 'Webhooks by Zapier'
- Works with Make, n8n, Pipedream, custom backends
- Filterable event subscriptions
- Public API documented in /docs/PUBLIC_API
FAQ
Is there an official Glo Invoice Zapier app?
Not yet — today, integration goes through 'Webhooks by Zapier' against our public API and webhooks, which covers every Zapier-compatible workflow.
Where do I get an API key?
Admin → API Keys. Generate, copy once, and use as a bearer token on API calls or as auth on webhook receivers.
What events can fire a webhook?
Invoice sent / paid / overdue, estimate sent / approved, payment received, customer created, and more. Subscribe per-event from Admin → Webhooks.
Can I build my own automations without Zapier?
Yes. The same API and webhooks work with Make, n8n, Pipedream, or your own backend.
Start invoicing free
Send your first invoice in under a minute. Cancel anytime.