Melso

Being self-employed in Spain means quarterly VAT and income tax returns, VERI*FACTU-compliant invoices and a steady stream of expense receipts. Melso splits that work between software and people. An AI agent, reachable on WhatsApp or in the web app, handles the day-to-day: you might send a voice note asking for an invoice to a client for website design, and it comes back with a draft that already shows VAT and the IRPF withholding. You approve the exact version before it is issued. Expenses can be sent as photos or messages, pulled from invoices the agent finds in your connected Gmail or Google Drive, and turned into categorised records. Ask for a monthly summary and you get income, expenses by category and a PDF report.

The returns themselves are handled by Melso's tax professionals. They prepare and review the included Spanish returns, such as the quarterly Form 303 and the annual Renta, you approve the draft in the app, and they file it with the AEAT and send back the official receipt. The site says that if Melso's mistake causes a surcharge or penalty, Melso pays it.

Autónomos in Spain, including people who aren't registered yet, since registration is included in the plan, and people switching from a gestoría. The FAQ says you don't need Spanish. The agent answers in English on WhatsApp and the app works in English, though the forms are Spanish and you can ask about any box before approving. Developers and AI users can connect Claude or other assistants through Melso's MCP server to query expenses or draft invoices from a chat, with tax returns still approved inside Melso.

Melso Pro is 49 euros a month with no commitment, and new customers pay 24.50 for the first month. The plan covers autónomo registration, quarterly and annual returns, unlimited invoices and expenses, replies to tax agency notices about returns Melso filed, the WhatsApp agent and support.

Because the service handles tax IDs, bank details and invoices, the privacy policy matters, and Melso's version is specific. Melso, Inc. runs the service. Its AI uses Anthropic's Claude with zero data retention at the provider, plus OpenAI models for invoice extraction, served through AWS Bedrock, and customer content isn't used for training. Tax data goes to the assigned professionals and the AEAT, invoicing data to Invopop for e-invoicing, and WhatsApp messages travel through Meta's service. Melso normally keeps tax records and uploaded invoices for four years after the relevant deadline, and issued invoices for at least six years to meet legal and tax obligations.