> ## Documentation Index
> Fetch the complete documentation index at: https://docs.melso.ai/llms.txt
> Use this file to discover all available pages before exploring further.

> ## Agent Instructions
> Melso MCP: https://mcp.melso.ai/mcp (OAuth; one company per connection). Documentation-search MCP: https://docs.melso.ai/mcp; it does not act on customer accounts.
>
> Use the live tool list and respect company membership. Ask the person to approve the exact invoice or tax return version in the signed-in app. Melso's professionals prepare and file included returns after approval; an AI assistant does not file. A prepared file or an approval is not evidence of filing: only the AEAT's reference and receipt are. Keep credentials out of chat and logs.

# ERPs and invoicing software

> Your product holds the invoices and books. Melso turns them into VERI*FACTU registrations, VAT returns, corporate tax and a professional who files.

An ERP or an invoicing tool already has the data a gestoría asks for every
quarter. With the Melso API, the quarter closes itself: Melso reads the data
where it is, calculates the returns, and its professionals file them after the
company approves.

## Bring the history

A new company comes with its past. Three live capabilities load it without
retyping:

| What you have | Call | Result |
| - | - | - |
| Issued and received VAT books (CSV, ContaPlus CSV, XLSX) | [Import a VAT book](/api/reference/accounting/save-vat-book-import) | Income and expenses, skipping invoices already recorded |
| A journal from another program | [Import a journal](/api/reference/accounting/save-journal-import) | Melso's books continue from it, entry by entry |
| Bank statements (Norma 43, CSV, XLSX, PDF) | [Save a bank statement](/api/reference/banking/save-bank-statement) | Movements, with reconciliation proposals |

Each import has a read step that shows what the file holds before anything is
saved.

## Keep it current

| As it happens in your product | Call |
| - | - |
| A sales invoice is issued in your ERP | [Record an income](/api/reference/income/create-income) |
| A purchase invoice arrives | [Record an expense](/api/reference/expenses/create-expense), or [read the document](/api/reference/documents/extract-fiscal-document) |
| The company wants Melso to issue instead | [Create an invoice draft](/api/reference/invoices/create-invoice), registered with VERI\*FACTU or TicketBAI when the owner issues it |

## What closes each period

| Period | Returns Melso calculates | Live capability |
| - | - | - |
| Quarter | 303 VAT, 130 (autónomos), 111 and 115 withholdings, 349 intra-community | Yes |
| Year | 390, 347, 190, 180 | Yes |
| Year, empresas | Corporate tax 200 from the books, 202 instalments, trial balance, profit and loss, balance sheet | Yes |

Every return comes with its boxes and what to review. The 303, 130, 111 and
115 also come with their AEAT import file. The company's owner approves the
exact version and Melso's professionals file it. See
[Approvals and filing](/api/approvals).

## VERI\*FACTU

An invoice Melso issues is registered with the AEAT's VERI\*FACTU system, or
with TicketBAI in Álava, Bizkaia and Gipuzkoa, and its legal PDF carries the
registration. If your ERP issues the invoice itself, it stays your
responsibility to register it; record it in Melso as income so it counts in
the returns.

## Get started

Write to [hello@melso.ai](mailto:hello@melso.ai) with the export formats your
product produces today.


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