Invoice for a partner

Use a seller profile when your company produces an invoice in a partner’s name and for the partner’s account. The partner is the legal seller. Payment goes to the partner. The sale does not enter your ledger.

Before the first invoice

Prepare the partner through REST, MCP, or Invoicing → Partners. A company admin must then review and activate it in Invoicing → Partners. Activation requires:

registered legal name, Finnish business ID, and postal address;
the partner’s own IBAN and bookkeeping-copy email;
signed mandate reference and KYC reference.

A write-scoped REST or MCP credential can create and update the draft. It cannot approve its own evidence, activate the partner, or change an active partner. The same validation and audit rules apply to every route. For example, REST can prepare the draft in one call:

curl https://api.app.lastaccountingcompany.com/portal/seller-profiles \
  -H "Authorization: Bearer $LAC_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "legal_name": "<partner_legal_name>",
    "business_id": "<partner_business_id>",
    "street_address": "<partner_street_address>",
    "postal_code": "<partner_postal_code>",
    "city": "<partner_city>",
    "country_code": "FI",
    "iban": "<partner_iban>",
    "contact_email": "<partner_bookkeeping_email>",
    "mandate_evidence_ref": "<signed_mandate_reference>",
    "kyc_evidence_ref": "<identity_check_reference>"
  }'

Add or correct draft fields with PATCH /portal/seller-profiles/{profile_id}. The company admin then verifies that LAC holds the evidence and selects Start using this partner in the portal.

1. Get the seller profile

Use a write-scoped key because the result contains bank and evidence references.

curl https://api.app.lastaccountingcompany.com/portal/seller-profiles \
  -H "Authorization: Bearer $LAC_API_KEY"

Select a profile whose status is active. Copy its id to the draft’s seller_profile_id.

2. Resolve the buyer’s e-invoice route

Search by the buyer’s name, Finnish business ID, or FI VAT ID. LAC asks Maventa for the current OVT/e-invoice address and operator; you do not create a receiver record.

curl --get https://api.app.lastaccountingcompany.com/portal/invoice-receivers \
  -H "Authorization: Bearer $LAC_API_KEY" \
  --data-urlencode "query=<buyer_business_id_or_fi_vat_id>"

Copy the returned einvoice_address and operator to the draft’s customer.

3. Create the draft

curl https://api.app.lastaccountingcompany.com/portal/invoices \
  -H "Authorization: Bearer $LAC_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "seller_profile_id": "selp_...",
    "delivery_channel": "maventa_einvoice",
    "issue_date": "<YYYY-MM-DD>",
    "terms_days": 14,
    "customer": {
      "name": "<buyer_legal_name>",
      "business_id": "<buyer_business_id>",
      "country_code": "FI",
      "einvoice_address": "<from recipient search>",
      "einvoice_operator": "<from recipient search>"
    },
    "lines": [{
      "description": "Consulting services",
      "quantity": "1",
      "unit_price_cents": 100000,
      "vat_rate_basis_points": 2550,
      "net_cents": 100000,
      "vat_cents": 25500,
      "gross_cents": 125500
    }],
    "net_cents": 100000,
    "vat_cents": 25500,
    "gross_cents": 125500
  }'

Set the VAT treatment from the underlying sale. The example rate shows the input shape only. Read the returned draft with GET /portal/invoices/{draft_id}. Confirm seller_profile_id, partner legal name, business ID, and IBAN before issue.

Consumer buyers and PDF delivery

For a consumer, use the customer-directory id returned by LAC when updating an existing buyer. A Business ID and e-invoice route are not required for the PDF channel.

{
  "seller_profile_id": "selp_...",
  "delivery_channel": "pdf_download",
  "customer": {
    "name": "<consumer_name>",
    "email": "<consumer_email>",
    "country_code": "FI"
  }
}

Finalize that draft with POST /portal/invoices/{draft_id}/finalize. The response includes pdf_document_id, pdf_sha256, pdf_size_bytes, and pdf_available=true. Download the exact retained bytes from GET /portal/invoices/{invoice_id}/pdf; its ETag and X-Content-SHA256 headers equal pdf_sha256. LAC keeps that immutable PDF as accounting evidence. You can attach the downloaded PDF to your own email, or host it behind your own authenticated link and send that link by text message. Finalizing does not send anything to the consumer. A consumer e-invoice still requires the consumer to have activated e-invoicing with their bank and supplied the corresponding receiving route. The PDF flow does not require that subscription.

4. Send

curl -X POST https://api.app.lastaccountingcompany.com/portal/invoices/invd_.../send \
  -H "Authorization: Bearer $LAC_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{}'

If invoice approval is required, call /request-approval first and wait for a person to approve it in the portal. The send has these fixed effects:

the Finvoice seller, postal address, business ID, VAT identity, invoice series, and payment IBAN come from the partner profile;
the tenant’s Maventa address is the technical material-handler route, not the legal seller;
the partner receives a PDF copy for its own books;
posts_ledger=false: no tenant journal, output VAT, receivable, aging, or overdue item is created.

MCP

Use create_seller_profile and update_seller_profile to prepare the draft partner. A company admin activates it in the portal after checking the evidence. Then use list_seller_profiles, search_invoice_receivers, create_invoice_draft, get_invoice, and send_invoice. MCP uses the same draft and customer fields as REST, but it does not expose the seller-profile status field. For recovery, use retry_invoice_send only after a safe failure. Use retry_partner_invoice_copy only after you verified that the partner did not receive an ambiguous earlier copy. LAC refuses ambiguous e-invoice sends until the outcome is checked in Maventa.

Getting started

Guides

MCP

Before the first invoice

1. Get the seller profile

2. Resolve the buyer’s e-invoice route

3. Create the draft

Consumer buyers and PDF delivery

4. Send

MCP

​Before the first invoice

​1. Get the seller profile

​2. Resolve the buyer’s e-invoice route

​3. Create the draft

​Consumer buyers and PDF delivery

​4. Send

​MCP

Before the first invoice

1. Get the seller profile

2. Resolve the buyer’s e-invoice route

3. Create the draft

Consumer buyers and PDF delivery

4. Send

MCP