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Lithuania · Agentic SaaS development

SaaS Development for Founders Building in Lithuania

Every business with a Lithuanian VAT registration, foreign entities included, must send data from its registers of issued and received VAT invoices to the State Tax Inspectorate's i.SAF subsystem every month, by the 20th of the following month, as XML in the i.SAF schema. Non-conforming files are rejected. If billing produces messy invoice data, that becomes a monthly repair job, so tax, payments and e-invoicing are product requirements here.

Curiosive builds subscription products from Ankara, Türkiye, with AI coding agents whose every change a senior engineer reviews. The agents write the CRUD screens, admin views, migrations and test suites. Engineers design the multi-tenant data model, tenant isolation, billing webhooks and plan logic, since that is where a SaaS leaks one customer's data to another or charges the wrong account. You own the code from the first commit.

Start a partnershipFrom $2,000 per month
24
published portfolio projects
5+
years building for production
12
countries the work runs in
100%
of code read by a senior engineer
1 day
to hear back, from the engineer

VAT, OSS and invoice reporting for SaaS sold from Lithuania

The standard VAT rate is 21%. Selling to businesses in other EU countries, you usually do not charge VAT: the customer pays at its own country's rate under the reverse charge, although there are several important exceptions. Electronic services sold to consumers in other EU countries are taxed in the customer's country, although below a EUR 10 000 threshold they may be taxed where the seller is established, and the One Stop Shop lets you declare that VAT through one registration. Billing therefore has to store each customer's country, business or consumer status and VAT number, and each invoice must carry the right treatment. Council Directive (EU) 2025/516 (ViDA) makes European-standard e-invoices the rule from 1 July 2030, with reverse-charge invoices due within 10 days of the chargeable event. It is worth confirming your set-up with an accountant.

Card and bank payments in Lithuanian SaaS checkouts

In the ECB's SPACE 2024 survey, cards accounted for 48.7% of the number of online payments made by Lithuanian consumers. Wallets and other e-payment solutions were only 12.6%, against 28.6% across the euro area, while credit transfers, direct debits and instant payments together reached 29.6%. So the checkout should lead with cards and offer bank-based payment second. Strong customer authentication has applied under the PSD2 technical standards since 14 September 2019; a provider may skip it for a remote payment of no more than EUR 30 only while the payer's remote payments since the last authentication stay within a cumulative EUR 100 or five consecutive transactions. Renewals and failed authentications need their own handling. Subscription status comes from the payment provider's webhook events, each handler is idempotent so a redelivered event changes nothing, and a person reviews every change to a payment path.

Selling to public bodies and businesses in Lithuania: SABIS and eID

If your customers include public-sector bodies or other contracting authorities, invoices go through SABIS, run by the National Centre for Shared Functions. It launched in 2024, replaced the earlier 'E. sąskaita' system, requires invoices that meet the European e-invoicing standard and connects to the Peppol network. For login and signing, the Communications Regulatory Authority (RRT) has supervised qualified electronic identification means since 2 January 2024. Its list covers Smart-ID and Mobile-ID at assurance level high, LT ID at substantial and the Paysera Mobile App, registered by RRT order of 29 January 2026. For admin login or contract signing in a B2B product, one of these is an option worth weighing.

Accessibility law and Data Act switching duties for SaaS vendors

Lithuania transposed the European Accessibility Act through Law No. XIV-1633 on accessibility requirements for products and services, in force since 28 June 2025, with its current consolidated version applying from 30 June 2026. The Act covers consumer services such as e-commerce, consumer banking, e-books and dedicated software, while microenterprises, meaning fewer than 10 persons employed and an annual turnover or balance sheet total of no more than EUR 2 million, are exempt from the service requirements. The EU Data Act has applied since 12 September 2025, and its recitals place SaaS among data processing services. Switching terms need a written contract, a notice period of no more than two months and a transitional period of no more than 30 calendar days, with only reduced switching charges until 12 January 2027 and none after. Your export features need to support that.

Multi-tenant SaaS architecture: what agents build and engineers own

Tenant separation is decided by an engineer before an agent writes a single screen. Every query is scoped to a tenant, plans and entitlements are read from one place, and billing state comes from the payment provider's events, never from a second copy inside the app. On those foundations, Claude Code or Cursor produces the CRUD screens, admin views, migrations and tests, and none of it merges without senior review. Reveal Software, personal video onboarding for SaaS products, built for a client in Romania, uses the same PostgreSQL, Drizzle ORM, Hono and Next.js stack. With eight or nine office hours shared with Ankara depending on the season, a tenant rule or a billing edge case can be settled on a call inside both teams' office hours.

Proof

Published project examples

Reveal Software

Reveal Software

Release Coach AI

Release Coach AI

Inspire Film

Inspire Film

Poppin

Poppin

Zing Coach

Zing Coach

ChurchBee

ChurchBee

AI-accelerated development
from$2,000
per month

Senior engineers building your product with AI coding agents: web, mobile, SaaS or browser extension, reviewed before anything ships.

  • Web, mobile, SaaS and browser extensions
  • AI-assisted delivery under senior engineer review
  • Scope and capacity agreed in writing, renews monthly

AI-accelerated development, billed monthly. We confirm scope, capacity and start date in writing before checkout.

Questions

The things people ask before starting.

What VAT rate applies to SaaS sold in Lithuania?

Lithuania's standard VAT rate is 21%. Business customers in other EU countries usually pay VAT at their own country's rate under the reverse charge, with several important exceptions. Sales to consumers elsewhere in the EU are generally taxed in the customer's country and can be declared through the One Stop Shop.

Do SaaS invoices in Lithuania have to be electronic?

For public-sector customers, yes: invoices must go through SABIS and meet the European e-invoicing standard. If you are VAT-registered in Lithuania, your invoice registers also go to i.SAF every month. From 1 July 2030 the ViDA directive makes European-standard e-invoices the rule, and cross-border reverse-charge supplies cannot fall back to paper.

Which payment methods should a Lithuanian SaaS checkout support?

Cards first, then bank-based payments. In the ECB's SPACE 2024 survey, cards were 48.7% of consumers' online payments by number there, while wallets were only 12.6%, well below the euro area's 28.6%, so a checkout that leads with wallets misreads how people pay.

Can a non-EU founder start a SaaS company in Lithuania?

Yes, through Startup Visa Lithuania. Run by Startup Lithuania, it gives innovative non-EU founders a two-year temporary residence permit, with a chance to extend it to five years. Founders apply online, pitch in a 30-minute video interview and must register the company within 120 days of receiving the permit.

Does the Data Act switching chapter apply to a SaaS built for one customer?

Not in full. Under Article 31, several switching obligations, including the rules on switching charges, do not apply to a service mostly custom-built for one customer and not offered at broad commercial scale through the provider's service catalogue. The provider must tell the customer which obligations do not apply before the contract is concluded.

Related pages

Solutions
Locations

Mobile App Development for Lithuania's Android-Heavy Market

Locations

Software Development Partner for Teams in Lithuania

Services

Agentic SaaS Development: Multi-Tenant Subscription Products

Locations

SaaS Development for Luxembourg: Billing, VAT and Access

How it starts

What happens after you write to us.

  1. 01

    You describe the product

    One paragraph on what you are building, roughly when you need it, and who it is for. No brief, no form with fifteen fields.

  2. 02

    You get a reply within a day

    From the engineer who would do the work, not a sales team. If we are not the right fit we say so, and where possible we point you somewhere better.

  3. 03

    You get a scoped plan

    Scope, price and timeline in writing before anything is committed. You decide with the numbers in front of you.

No long contract to begin, no lock-in to our tooling, and the code is yours from the first commit.

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Contact

Looking for an engineering partner for the long haul?

A short note about the product, the timeline and who it is for is enough to start. You will hear back from the engineer who would do the work, not a sales team.

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Ankara / Türkiye · Working across European and US time zones