# Invoicing {#invoicing}


Create, send, and manage invoices and estimates with support for multiple currencies, taxes, and discounts.


## Invoice Features {#invoice-features}


- **Custom invoice numbers** with auto-increment
- **Multiple line items** with quantity, rate, and description
- **Tax calculations** (single or dual tax rates)
- **Discount support** (percentage or fixed amount)
- **PDF generation** for email and download
- **Email delivery** directly from the platform
- **Status tracking** from draft to paid
- **Multi-currency** support


## Invoice Lifecycle {#invoice-lifecycle}


```
DRAFT → SENT → VIEWED → ACCEPTED → PAID
  │       │                          ↑
  │       └── OVERDUE ───────────────┘ (partial payment)
  │
  └── VOID (cancelled)
```


## Invoice Items {#invoice-items}


Each invoice contains line items:

| Field           | Description                 |
| --------------- | --------------------------- |
| `description`   | Item/service description    |
| `quantity`      | Number of units             |
| `price`         | Rate per unit               |
| `totalValue`    | quantity × price            |
| `applyTax`      | Apply tax to this item      |
| `applyDiscount` | Apply discount to this item |


### Item Types {#item-types}


Invoices can itemize different sources:

| Type            | Description                 |
| --------------- | --------------------------- |
| **By Task**     | Bill for tracked tasks      |
| **By Employee** | Bill for employee hours     |
| **By Project**  | Bill for project milestones |
| **By Expense**  | Reimburse marked expenses   |


## Estimates {#estimates}


Estimates use the same system with `isEstimate: true`:

- Create estimates for potential work
- Send estimates to clients for approval
- Convert approved estimates into invoices
- Track estimate acceptance rates


## Permissions {#permissions}


| Action                | Permission       |
| --------------------- | ---------------- |
| View invoices         | `INVOICES_VIEW`  |
| Create/edit invoices  | `INVOICES_EDIT`  |
| View estimates        | `ESTIMATES_VIEW` |
| Create/edit estimates | `ESTIMATES_EDIT` |


## Related Pages {#related-pages}


- [Invoice Endpoints](https://sourcey-gauzy.pages.dev/api/invoice-endpoints/index.md) — API reference
- [Payments](https://sourcey-gauzy.pages.dev/features/payments/index.md) — payment recording
- [ERP Overview](https://sourcey-gauzy.pages.dev/features/erp-overview/index.md) — ERP module overview