Third-party invoicing

Számlázz.hu supports invoice issuing in two main models: standard invoicing (the supplier issues the invoice to the buyer) or delegated (third-party) invoicing. The latter has two variants: classic delegated invoicing (a third party authorised by the supplier issues the invoice to the buyer from the supplier's account) and self-billing (the buyer issues the invoice to itself in the supplier's name, from the supplier's account; in other words, the supplier authorises the buyer to issue the invoice). This page helps you decide which model your process belongs to, and summarizes what you need to know to get started:

• the roles and terminology (supplier, delegate, buyer),
• what is important to know before you start (costs, prerequisites),
• the two ways to establish the connection (in the UI or via API),
• and the next steps, from test mode to live use.

The diagram answers the same question for all three setups: who issues the invoice (left, orange), in whose name and account it is created (middle, yellow), and who receives it (right, blue).

Roles and terminology

• Supplier (megbízó): the company in whose name the invoices are issued. The invoices belong to the supplier's Számlázz.hu account.
• Delegate (megbízott): the company that issues the invoices in the supplier's account, with a dedicated user. The costs of delegated issuing are charged to the delegate.
• Buyer (vevő): the customer on the invoice. In delegated invoicing, the buyer can be any third party; in self-billing, the buyer is the delegate company itself.

Important to know before you start

Before you start, clarify who pays what, what is required legally and technically, and which account state allows live invoicing.

Who bears the costs

• The supplier pays the plan of their own Számlázz.hu account, as before; the system usage costs of delegated issuing are not charged to them. A delegated join request can be accepted on any plan, even in a #free supplier account.
• The delegate bears the costs of delegated issuing: the service has a fixed monthly fee, payable in arrears, independent of the number of suppliers the delegate invoices on behalf of. On top of that, the fees of bulk invoicing or the Számla Agent (if used) are also charged to the delegate as variable costs. Current pricing is on the product page (Hungarian): Megbízott számlakibocsátás és önszámlázás.

With test accounts, the combinations work as follows:

Delegate account	Supplier account	What happens
Live	Test	Documents created in the supplier's test account are test documents: they are not submitted to NAV, and no delegated-issuing fee is charged for them.
Test	Test	This is the recommended test setup: a supplier account created via API is automatically a test account. No fee is charged; the test documents are deleted when the account goes live.
Test	Live	Setup to avoid: live documents would be issued in the live supplier account. For live delegated invoicing, switch your delegate account to live first; the test account is meant for trying things out only.

Prerequisites and things to agree in advance

• Before delegated invoicing starts, a written authorisation is required between parties; this is a step outside Számlázz.hu.
• A completed NAV Online Számla connection is required in the supplier account before live invoicing.
• If you plan to use the Számla Agent to create the supplier account or to send the join request: the action-agent_ceg_mb API interface requires a licence / permission; request it from customer support in advance.
• If you create the supplier account via API, it becomes invoice-ready after ownership is taken and approval is completed.
• Suppliers typically request a separate invoice book/prefix for delegated issuing, so it is best to agree this in advance. See Invoice prefix handling.

info

The setup path depends on whether the supplier already has an invoicing account. If yes, the connection is established with a join request (in the UI or via API); if not, the flow starts with account creation, which is API-only (action-agent_ceg_mb) - or the supplier registers an account themselves.

Connection paths: UI or API

The delegated connection between the two companies can be established in two ways; the result is the same (a dedicated delegated user in the supplier's account), so choose based on your situation:

	In the UI (control panel)	Via API (action-agent_ceg_mb)
Best for	A few suppliers, manual onboarding	Many suppliers, automated onboarding
Supplier account	Must already exist (or the supplier has to register before the connection is initiated)	Can be created by the call, or a join request is sent to an existing account
Who acts	The delegate sends a join request from their own account	The delegate posts an XML request
Requirements	Registered accounts on both sides	Registered delegate account + licence / permission from support
Approval	The supplier accepts on the dashboard	The supplier accepts on the dashboard (or takes ownership of the new account)
Details	Establish the connection in the UI	Establish the connection via API

The existing supplier account is recognized by the tax number

On the API route the system decides whether the supplier already has an account based on the tax number sent in the call. If the tax number does not exactly match the one stored in the existing account (for example because of a typo), the call does not send a join request but creates a new account instead. Before submitting, always double-check that the supplier's details, especially the tax number, are given exactly in the request.

Next steps

Try it in test mode first

The whole flow can be tried risk-free with test accounts before going live. The knowledge base article on test API access (Hungarian) walks you through creating and using a test account. Conditions for enabling test mode ("Tesztüzem bekapcsolása" on the Dashboard):

• the account is on the #free plan,
• it has no live invoice or receipt yet,
• it has no completed NAV Online Számla connection.

tip

Do not subscribe to a paid plan for testing. Switch the account to test mode instead: a test account automatically gets the #profi feature set free of charge for the duration of the test.

Test documents are not submitted to NAV. When the account goes live (test mode is turned off), the documents created during testing are deleted. Details: Testing the flow.

Where to go next

Choose the path that matches your role:

• I invoice from my own account (API key): Számla Agent documentation or PHP API adapter module
• I issue invoices as the buyer (self-billing): Self-billing overview
• I issue invoices as a delegate for another company: Issue invoices in third-party invoicing

Self-billing: related pages

• Self-billing overview
• Establish the connection in the UI
• Establish the connection via API
• Issue invoices as self-biller

Delegated invoicing: related pages

• Establish the connection in the UI - connect to an existing supplier account from control panel.
• Establish the connection via API - create/connect supplier account via API (action-agent_ceg_mb).
• Issue invoices in third-party invoicing - operational issuing flow.
• Issue receipts in third-party invoicing - delegated receipt issuing.
• Invoice prefix handling - what happens with each prefix you send.
• Error handling - error codes specific to delegated invoicing.

tip

For a business overview, related pricing, and key details, use the official product page (Hungarian): Megbízott számlakibocsátás és önszámlázás.