How do we get B1.lt API access?

API access is enabled in your B1.lt account; if your plan doesn't include it, we check with B1.lt. We show you where to do it or, with your permission, do it ourselves. The access key is stored on the server and never shared with third parties.

Won't the invoice numbering get mixed up?

No, as long as you agree in advance which system does the numbering. We recommend that invoices for online store orders are numbered by one system – either B1.lt, or the online store with its own series. We agree the series and its starting number with your accountant before launch.

Does the integration work if our accountant works for another company?

Yes. Your accountant works in B1.lt as usual – they simply find the documents already created. We agree VAT rates, series and payment methods with them, and we can send notifications about failed transfers to them too, so they see any errors straight away.

What happens if B1.lt is unavailable at the time?

Nothing bad – the integration simply waits. The order stays in the queue and is sent again once B1.lt is back, and if it still fails after several attempts, you get an email notification. Checkout isn't affected, because the data is transferred in the background.

Will the B1.lt integration work with a VirtueMart store?

Yes. As well as WooCommerce, we integrate VirtueMart (built on Joomla) and custom Laravel online stores. If there is no ready-made module for your platform, we build the integration using the B1.lt API – in that case, we set the price after the check.

B1.lt integration with your online store

B1.lt integration connects this cloud-based Lithuanian accounting system with your online store, so orders, invoices, stock levels and payments are passed on automatically, without manual entry. Saitai.lt connects B1.lt with WooCommerce, VirtueMart and custom online stores. A ready-made module or configuration costs from €490; a custom integration is quoted after assessment.

Get a quote How much does it cost?

Prepared by the Saitai.lt team · Updated 6 October 2026

In short

Price: from €490 (ready-made module or configuration); custom API integration quoted after assessment; no VAT is added
Timeline: 1–2 weeks (ready-made module); 2–4 weeks (custom integration)
How it connects: B1.lt runs in the cloud, so data travels over the internet – nothing needs installing on an office computer
Online stores: WooCommerce, VirtueMart, custom online store (Laravel)
What is transferred: orders, invoices, customers, products, prices, stock levels, payment statuses
Warranty: 12 months
Payment: 50% deposit, balance when the integration goes live
Where we work: remotely, all over Lithuania; meetings in Vilnius by appointment, arranged by phone

Who it’s for

You issue invoices to customers in B1.lt by hand, copying the details from each online store order.
Your bookkeeping is done by an outside accounting firm, and it only receives your orders at the end of the month as an Excel file.
Stock levels in B1.lt and in your online store don't match, because sales are recorded at different times.
You sell online and through other channels, and every sale has to end up in the same set of accounts.
Customers need their invoice as soon as they have paid, not a few days later when the accountant gets round to issuing it.
You are starting to sell online and want your accounting automated from the very first order.

When it’s not the right fit

You only get a few orders a month. Then it's cheaper to issue the invoice in B1.lt by hand than to pay for an integration.
You don't want to give the online store access to your accounting data. Without API access, automatic exchange isn't possible – what remains is a periodic file import, if that suits your accountant.
You expect the integration to prepare your VAT return or i.SAF file (the Lithuanian VAT invoice register). That is your accountant's job in B1.lt; the integration makes sure every sale gets there.

Diagram of a B1.lt online store integration: invoices after payment, customer and company details, products and stock levels, and payment statuses are transferred automatically

Included

What you get

API access set-up

We help you enable API access in your B1.lt account. The access key is stored on the server, not in the browser, and is never shared with third parties.

Invoices once an order is paid

When an order is paid, an invoice with the customer, products, VAT and delivery is created in B1.lt, and its number or PDF can be sent to the customer.

Customer and company details

Details of private customers and companies, including company codes and VAT numbers, are transferred so that invoices follow your accountant's procedures and customers aren't duplicated.

Products and stock levels

Stock levels from B1.lt are updated in the online store on a schedule, and new products can be created as drafts for you to complete with descriptions.

Payment statuses

If the integration includes it, a payment confirmed by the payment provider is also marked in B1.lt, so your accountant doesn't have to match it against the bank statement by hand.

Error log and automatic retries

A failed transfer is logged and retried, and if it still fails, the person responsible gets an email explaining why.

Guide and a 12-month warranty

We hand over a short guide to you and your accountant. For 12 months, we fix integration bugs free of charge.

Price

How much does a B1.lt online store integration cost?

Price from

€490

Integrating B1.lt with an online store costs from €490 when a ready-made module exists for your platform, or the solution only needs configuring. A custom API integration – for example, when you need several online stores, B2B prices or non-standard invoicing rules – is quoted separately once we have checked your B1.lt settings.

Prices include all taxes – no VAT is added (we are not VAT-registered). The final price depends on the project: we put it and the timeline in the contract before work starts.

Get an exact price

What the price depends on

Whether a ready-made B1.lt module exists for your online store platform.
Who issues the invoices – B1.lt or the online store – and how their numbering is coordinated.
Whether you need to transfer only orders, or products, stock levels and payments as well.
How many VAT rates, payment methods and delivery methods need mapping.
Whether you sell only to private customers, or to companies and customers abroad as well.
Whether several online stores or sales channels need connecting.

Additional costs

A fee for the B1.lt plan or API use, if the software provider charges one – paid directly to the provider.
Payment or shipping provider integration, if you need it at the same time – from €150 per provider.
Integration maintenance after the warranty, and new data flows – under a separate agreement, confirmed in writing.

Timeline

How long does a B1.lt integration take?

An integration with a ready-made module takes 1–2 weeks, and a custom API integration 2–4 weeks from receiving the deposit and API access. As B1.lt runs in the cloud, nothing has to be installed on an office computer, so most of the time goes on mapping the data and testing.

Scope	Example	Timeline
Invoices from orders	a paid order becomes an invoice in B1.lt	1–2 weeks
Two-way exchange	plus stock levels and prices from B1.lt to the online store, and payment statuses	2–3 weeks
Custom integration	several online stores, B2B prices, returns, customers abroad	3–4 weeks

Process

How it works

Free consultation1–2 working days
We talk through who issues invoices now and when, which platform your online store runs on, and whether your accounts are kept in-house or by an outside accountant.
Check and fixed price1–3 working days
We check the B1.lt API options available in your account and any existing modules. The price and timeline go into the contract, and we start once we receive the 50% deposit.
Agreeing the invoicing rules1–3 working days
With your accountant, we agree the invoice series and numbering, VAT rates, product codes, and payment and delivery methods.
Configuration or development3–10 working days
We install the module or build the integration, and set up the sync schedule and error notifications.
Testing2–5 working days
We test the integration with sample orders: a private customer, a company, an order with a discount and a return. We agree with your accountant in advance how test documents will be told apart.
Launch and monitoring1–5 working days
We switch the integration on from a new invoice series or the start of a month, and check the log daily for the first week.
Warranty and maintenance12 months
For 12 months, we fix integration bugs free of charge. If B1.lt changes its API, we adapt the integration under a maintenance agreement.

Comparison

Who issues the invoice: your accountant, the online store or B1.lt?

Criterion	Issued by hand	Invoice from the online store	Invoice from B1.lt (integration)
How it works	the accountant issues the invoice in B1.lt based on the order	the online store issues and sends the invoice, and the integration passes the data to B1.lt	B1.lt creates the invoice, and the online store receives its number or PDF
When the customer gets the invoice	whenever the accountant issues it	immediately after payment	shortly after payment, once the invoice has been created in B1.lt
Numbering	B1.lt series	a separate online store series	one B1.lt series for all channels
Price	€0, but every order needs manual work	from €490	from €490
What to watch out for	delays and copying errors	the series must not overlap with B1.lt series	if the connection drops, the invoice is created on the next retry
Best for	a few orders a month	when the online store already issues invoices and that works well	several sales channels and a single numbering sequence

Examples

Typical scenarios

Handmade jewellery store

Situation: For example, a small handmade jewellery store gets several hundred orders a month. Every evening, the owner issues invoices in B1.lt and emails them to customers.
Solution: When an order is paid, an invoice is created in B1.lt automatically, and its PDF is attached to the email to the customer.
Result: Free evenings, invoices sent to customers straight away and tidy paperwork for the accountant.

Online store with an outside accountant

Situation: For example, a sports goods store has its accounts kept by an accounting firm. At the end of each month, the firm is sent a file of orders, and queries about missing invoices take several days to resolve.
Solution: Orders and payments reach B1.lt automatically, so the accountant sees the documents the same day and only needs to check them at the end of the month.
Result: A faster month-end close, less back-and-forth and a clear trail for every order, from payment to invoice.

Plant store selling online and at fairs

Situation: For example, a plant store sells online and at fairs. Sales at fairs are recorded in B1.lt, while the owner corrects online store stock levels by hand.
Solution: B1.lt becomes the single source of stock levels: online store sales reach it once paid, and combined stock levels are updated in the store on a schedule, for example every 30 minutes.
Result: Matching stock levels across all sales channels and fewer orders that have to be cancelled.

Tell us how you issue invoices today

Let us know your online store platform, how many orders you get a month and who keeps your accounts in B1.lt. Within 1 working day, we'll tell you what kind of solution you need, how much it would cost and how long it would take.

Get an estimate

FAQ

Frequently asked questions

No. B1.lt runs in the cloud, so the integration connects to it over the internet via its API. You don't need to install anything in the office or keep a computer switched on – the online store just has to be running. This is what sets it apart from integrations with accounting software installed on a computer, which often need an intermediary program.

More

Get a B1.lt integration quote within 1 working day

Tell us which platform your online store runs on, how many orders you get and who issues your invoices. Tel. +370 670 99265.

Phone / WhatsApp / Viber:
+370 670 99265

Email:
info@saitai.lt

We reply within 1 working day. Meetings in Vilnius are by appointment only – please call first.