ERP system for small businesses: off-the-shelf or custom, and what it costs

The best way to get an ERP system for a small business is to buy an off-the-shelf one (on a subscription or under a licence model) and to build your own system only for the part of the work that ready-made software cannot handle without workarounds and spreadsheets kept alongside it. According to the official price lists, the Podstawowy (Basic) module of Comarch ERP Optima costs €14 net (excl. VAT) a month per seat (with a limit of 20 sales documents a month), and Symfonia ERP w Chmurze (the cloud edition) costs €110 net (excl. VAT) a month per user. On top of that come further modules, support for KSeF, Poland's National e-Invoicing System, and implementation, the price of which you usually agree with an implementation partner, i.e. a company that sells and implements the system in question.

Euro amounts converted at the NBP mid-market rate of 14 September 2026 (€1 = 4.3391 zł) and rounded. We invoice in PLN.

With a custom-built ERP system you pay neither per user nor for a licence, but for the build, calculated in hours and billed in stages, and then for the server and, if you want it, for ongoing support. At CodePort, a simple app or panel (user accounts, basic modules, admin panel) costs around €4,150–10,400 net (excl. VAT), and a large system integrated with ERP and CRM starts at around €23,000 net (excl. VAT). There is also a third route, which a small business should check first: stay with an off-the-shelf ERP and add the missing integrations. In an example calculated from the hours in our cost calculator (ERP, online shop and Allegro, Poland's largest online marketplace, with two-way synchronisation and error notifications), this costs €2,900–7,350 net (excl. VAT). A connection to KSeF, needed when invoices are created outside the ERP, is a separate item in the calculator: €1,100–2,750 net (excl. VAT), added to the integration project; if you select only that item, the calculator adds 12–24 hours for the project's architecture, logging and deployment and shows a total of around €1,600–3,900 net (excl. VAT).

We checked the vendors' prices on their official websites on 26 October 2026.

Does a small business need an ERP system, or is invoicing software enough?

An ERP is a single system with a single database for sales, warehouse, purchasing and finance, and often for HR and payroll too. It pays off when these areas work on the same documents and someone currently retypes data from one application to another.

If your company mainly issues invoices and an accounting firm keeps your books, invoicing software or online accounting is usually enough. Symfonia itself writes that simple off-the-shelf systems for invoicing, bookkeeping and basic warehouse management can cost a few hundred zloty a year on subscription. A full ERP makes sense when a warehouse, several sales channels and several people working on the same stock levels and documents come into play.

How much does an off-the-shelf ERP system for small businesses cost?

For an off-the-shelf ERP you usually pay a fixed amount per seat or per user, either monthly or upfront for a year (vendors call this a subscription — in Polish, subskrypcja or abonament). The other option is to buy a licence with an annual fee for updates — at InsERT this fee is called Abonament. In the table we compare ERP systems for small businesses, giving the payment models in the vendors' own wording:

Odoo does not state whether its prices include VAT. Comarch and InsERT note that their price lists are not a commercial offer within the meaning of the Polish Civil Code, and Microsoft describes its prices as indicative, so with these vendors you will only learn the binding price from a quote.

What else affects the cost

As Symfonia itself points out, the cost of an ERP is not just the price of the software. Check:

• Implementation. Of the systems in the table, only Odoo publishes implementation prices: packages for new customers cost from €280 for 4 hours of a consultant's work to €9,180 for 200 hours. Odoo also points out that implementation is not included in the subscription.
• How people are counted. Comarch ERP Optima counts seats, i.e. the maximum number of people working in a module at the same time, while Symfonia ERP w Chmurze and Odoo count users. Under the Subiekt nexo PRO Abonament, each additional seat from the fourth onwards costs an extra €17 net (excl. VAT) a year.
• The price after the promotion. Odoo's discount applies for 12 months, and the Optima w Chmurze packages are available only with a first purchase of Optima. Calculate the cost using the prices that apply in the second and third year.
• KSeF fees. Comarch makes the price of its Comarch KSeF subscription depend on the annual number of documents (up to 200 a year — €3 net, excl. VAT, a month). The free period of communication with KSeF for customers with the subscription version of the ERP and for new customers ends on 31 December 2026, so for the following years include the full price of the KSeF subscription in your cost. InsERT's Abonament includes 100 InsPunkty (1 InsPunkt is the sending or downloading of one invoice), and a pack of 500 InsPunkty costs €46 net (excl. VAT). Symfonia KSeF Plus packages differ in their operation limit and, from 1 January 2027, also in their features.

How to calculate the cost of an off-the-shelf ERP over three years

(monthly price per seat or user × number of seats or users + monthly price of additional modules) × 36 months + KSeF for three years + implementation and training + integrations = cost of an off-the-shelf ERP over three years

If the vendor gives an annual price (e.g. InsERT's Abonament or Symfonia KSeF Plus), multiply it by 3, not by 36. Add a one-off licence (e.g. Subiekt nexo PRO) once.

Example (software cost only): Symfonia ERP w Chmurze for three users over 36 months is 3 × €110 × 36 ≈ €12,200 net (excl. VAT). If you handle KSeF with the Basic package of Symfonia KSeF Plus (€160 net, excl. VAT, a year), another 3 × €160 = €480 net (excl. VAT) is added over three years. We set out a similar formula for CRM in our article how much a CRM system costs.

How much does a custom ERP system cost?

Your own ERP system for a small business does not have to mean writing accounting and HR from scratch — and in our view it should not. It is usually a system for the part of the work that off-the-shelf software does not model, connected to your accounting software or ERP.

With us, an estimate is hours × rate: development €46/h net (excl. VAT), design €35/h net (excl. VAT). According to the price ranges on our page about web applications, a simple panel costs around €4,150–10,400 net (excl. VAT) and is usually built in 6–10 weeks. A platform with several modules, integrations, roles and permissions costs €9,200–23,000 net (excl. VAT) and takes 2–4 months. A large system with many roles, complex logic and integrations with ERP and CRM costs from around €23,000 net (excl. VAT); we build a system like that in stages.

An example from our cost calculator (an illustration, not an offer): a browser-based panel for running the company, 5–15 screens, interface design from scratch, accounts and login, an admin panel, notifications, search and a connection to an ERP or warehouse system (Subiekt, Comarch, BaseLinker), one language version, without the “Urgent” option, which raises the price by 20%. Result: around 220–530 hours, i.e. €9,700–23,400 net (excl. VAT) and 10–19 weeks — already the platform price range rather than that of a simple panel. We set out the hours for individual features in our article how much a web application costs.

On top of the build, add:

• KSeF, if invoices are to be created in this system: sending takes 24–60 hours (€1,100–2,750 net, excl. VAT), and together with receiving purchase invoices 38–100 hours (€1,750–4,600 net, excl. VAT). The ranges do not include the 12–24 hours for architecture, logging and deployment of the whole project, which have to be added; we explain how the calculator counts these items in the section on integrations below.
• Support after launch: monitoring, backups, updates and further development typically take 5–15 hours, i.e. €230–690 net (excl. VAT) a month, plus the server.

The system becomes yours once all stages have been accepted and all invoices paid: we transfer full intellectual property rights to the code and design, and the code goes into your repository.

How much does it cost to integrate ERP systems with an online shop, Allegro and KSeF?

The third route is to stay with an off-the-shelf ERP and add only the missing connections: to your online shop, a marketplace, your accounting software or KSeF. You then do not pay for building modules that the vendor already has.

We price ERP system integration like any other: hours × €46 net (excl. VAT). The price depends on the number of systems being connected, the quality of their API documentation (the API being the interface through which applications exchange data) and the number of exceptions to handle. Connection hours from our cost calculator (full table with add-ons: how much automation and integration cost):

The KSeF item covers the connection and sending or downloading invoices, without matching them. If downloaded purchase invoices are to be matched to the counterparty and the order, and credit notes handled, tick the “KSeF: receiving purchase invoices” add-on — together with the connection, that comes to 38–100 hours.

Every integration project, regardless of the number of connections, includes a one-off foundation (architecture, logging, error handling, deployment): 12–24 hours. When a system has neither an API nor documentation, the hours for connections increase by around 60%.

Example (an illustration, not an offer): an off-the-shelf ERP connected to an online shop and Allegro, with two-way synchronisation and error notifications, all systems with API documentation, without the “Urgent” option:

• foundation 12–24 h, ERP 16–44 h, online shop 10–26 h, Allegro 14–34 h,
• two-way synchronisation 8–24 h, error notifications 3–8 h,
• a total of 63–160 hours × €46 = €2,900–7,350 net (excl. VAT), around 4–8 weeks of work.

The cost calculator rounds amounts in steps equivalent to about €120 and hours to multiples of 5, so it will show around €2,900–7,350 net (excl. VAT) and 65–160 hours. Without an API and documentation, the same set comes to around €4,050–10,300 net (excl. VAT).

A bank connection is not a separate item in the calculator. Before you order one, check what the ERP itself offers: Optima w Chmurze has the Kasa/Bank Plus module, and the enova365 Nowa Firma PLUS package includes Elektroniczne Wyciągi Bankowe (electronic bank statements). An integration also needs ongoing support, because providers change their APIs: typically 5–15 hours a month.

When does a custom ERP system make sense, and when does it not?

A custom system makes no sense for accounting, HR and payroll: here all companies operate under the same regulations, and in off-the-shelf software it is the vendor who implements changes in the law. Nor does it make sense when your sales and warehouse work the way they do in most trading and service companies: Symfonia ERP w Chmurze states a set-up time of up to 2 days (implementation comes on top of that), while building your own panel from the example above takes 10–19 weeks.

It is worth drawing the line between the “regulatory” part and the operational part. Accounting, HR and payroll stay in off-the-shelf software. Orders, production, quotes or document workflow can be moved to your own system or handled with an integration or process automation if, in an off-the-shelf ERP, they require workarounds and spreadsheets kept alongside the system. We described the general signs that an off-the-shelf tool is no longer enough in our article no-code or custom software (in Polish).

How do you check whether an ERP system is ready for KSeF?

The word “KSeF” in a price list can mean very different sets of features. Ask about five things:

1. Sending. Does the system create the invoice in the FA(3) structure (the e-invoice schema in which KSeF accepts invoices), send it to KSeF and save the KSeF number against the document?
2. Receiving purchase invoices. Does it download them from KSeF and let you match them to the counterparty and the order?
3. Offline mode and KSeF failures. Does the system issue invoices in offline24 mode and during KSeF unavailability and failures, and does it then keep track of the deadlines for sending them? In offline24 mode the invoice must be sent to KSeF no later than the next working day after the day it was issued; during announced KSeF unavailability, no later than the next working day after the unavailability ends; and during a KSeF failure announced by Poland's Ministry of Finance, within 7 working days of the end of the failure. An invoice delivered to the buyer before it is sent to KSeF carries two QR codes; generating the second one requires a type 2 (offline) KSeF certificate. Comarch, for example, describes an offline mode in which an e-invoice with a QR code reaches KSeF once the connection is restored.
4. Fees from 1 January 2027. What is the document limit and how much will you pay after the free period? enova365 states that there are no additional fees for sending and receiving invoices.
5. All sales channels. Are invoices created only in the ERP? A ready-made module is enough when you issue invoices in an ERP with built-in KSeF support. Integration via the API is needed when invoices are created in your own system, online shop or panel — details in our article on KSeF integration with your own system, shop or ERP.

Deadlines: from 1 February 2026 every company, regardless of size, receives through KSeF the invoices that its business partners issued in KSeF. From 1 February 2026 invoices in KSeF are issued by companies whose sales in 2024 exceeded PLN 200 million (including VAT), and from 1 April 2026 by all other VAT payers. Until 31 December 2026, invoices can still be issued outside KSeF using fiscal cash registers, as can other invoices, provided that the total value of sales including VAT on invoices that would otherwise have to be issued in KSeF does not exceed PLN 10,000 (about €2,300) in a given month (invoices from cash registers and invoices for consumers do not count towards this limit). The invoice with which the limit is exceeded, and all subsequent ones, including those in the following months, must already be issued in KSeF. From 1 January 2027 these exceptions cease to apply.

Under the current rules, penalties for KSeF errors apply from 1 January 2027. On 20 October 2026 the Polish government adopted a draft act under which the penalty provisions would enter into force on 1 January 2028, meaning that no penalties would be imposed until the end of 2027. As at 29 October 2026, the draft is already in the Sejm (print no. 3245). The first reading took place on 21 October and the draft was referred to the Public Finance Committee; the committee has not yet issued its report, and the act has not been passed. Until the amendment enters into force, the current rules apply. The draft does not change the deadlines of the KSeF obligation itself. More in our article on KSeF penalties from 2027. We do not advise on tax matters — confirm the scope of your company's obligations with your accountants.

What should you check before signing a contract for an ERP system?

Apart from the price, ask about five things:

1. Who implements the system, and how are hours beyond the implementation package billed? Also ask how much you will pay in the following year: for additional users when your team grows, and per hour of the partner's work on changes after implementation.
2. Connections to your online shop, marketplace and bank. Are there ready-made connectors (connections to these applications available out of the box), and does your plan include API access? In Odoo's price list, the external API is listed under the Custom plan (€22.90 per user per month, billed annually; discounted price valid for 12 months; €27.90 without the discount), and the enova365 Nowa Firma PRO package includes, among other things, e-Sklep konektor and WebApi.
3. Data export. In what format will you export your product and business partner records, documents and history when you change systems? Export terms written into the contract protect you from being locked in to a single vendor.
4. Where the data is stored. Comarch ERP Optima w Chmurze runs in the Comarch Data Center in Kraków, while with Symfonia's desktop Finanse i Księgowość (Finance and Accounting) packages, installation, updates and server maintenance are on the user's side, i.e. your company's.
5. Legal updates and the Polish version. InsERT's Abonament covers, among other things, updates related to changes in the law. With global systems, ask who provides the Polish localisation and KSeF.

How do you prepare for an ERP system estimate?

The more precisely you describe your company, the narrower the price range will be. Prepare information about:

• modules: sales, warehouse, purchasing, production, accounting, HR, and which software each of them runs in today;
• users: how many people will work in the system and how many at the same time;
• systems: online shop, Allegro, accounting software, bank, and whether they have API documentation;
• the number of invoices issued and received per year, because the KSeF limits in price lists depend on it;
• data to be migrated: master records, stock levels, history.

You can check the cost of an integration or your own panel in the cost calculator: choose “System integration” or “Web application” — you will see the price range straight away, without giving your email address. You can describe the scope in the project brief builder, and we will prepare a detailed estimate with a schedule free of charge within 2–3 working days after a short conversation. If an off-the-shelf ERP with no add-ons is enough for your company, we will tell you so plainly.