RKSV Signature Card Replacement in Austria: ACOS-ID 2.1, FinanzOnline and May 2027

If your Austrian business uses a cash register with a physical RKSV signature card, now is the time to identify exactly which card is installed. Certification for the ACOS-ID 2.1 chip was not renewed because of the security issue known as “EUCLeak”. Austria’s Federal Ministry of Finance (BMF) states that these cards have, in principle, no longer met the legal requirements since 7 June 2025. Because replacement cards were not immediately available in sufficient quantities, a transition arrangement was introduced. The card replacement and its implementation in the cash register must be completed by May 2027.

This guide explains who is affected, the difference between ACOS-ID 2.1, CardOS 5.3, ACOS-ID 4.1 and online/HSM solutions, the practical FinanzOnline steps and when the deadline may be a useful trigger to review the wider POS setup. Information checked: 24 September 2026.

Which RKSV signature solutions are affected?

Why does ACOS-ID 2.1 need replacing?

The BMF explains that the relevant French certification body did not renew certification for the ACOS-ID 2.1 chip because of EUCLeak. This is more than an ordinary expiry event: it concerns the technical trust basis of the signature-creation unit used within the RKSV framework. The transition period gives businesses time to manage the change, but it does not turn the old card into a long-term solution.

What exactly does the May 2027 deadline mean?

May 2027 should not be treated as the point at which planning begins. The current BMF and WKO wording says the replacement and implementation must be completed by then. A realistic plan should include identifying the card type, ordering, checking compatibility, completing FinanzOnline steps, commissioning the new unit and testing normal receipt and daily-closing workflows.

Businesses using ATOS CardOS 5.3 should also plan ahead. WKO currently distinguishes it from ACOS-ID 2.1, but indicates that CardOS 5.3 will also become relevant by May 2027.

How to identify the signature card in your cash register

The age of the whole cash register is not enough. What matters is the actual SmartCard or signature-creation unit. Check your provider documentation, trust-service provider or cash-register supplier. For A-Trust cards, WKO notes that the SmartCard type can be viewed in the card management section of the a.sign Client.

• ACOS-ID 2.1: plan the replacement.
• CardOS 5.3: confirm the timeline to May 2027.
• ACOS-ID 4.1: not currently part of this specific replacement.
• Online/HSM: no physical card replacement for this reason.

What about tablet, mobile and app-based cash registers?

WKO explicitly distinguishes physical signature cards from online certificates and HSM solutions. Many cloud-based tablet, mobile or app registers use an online certificate. Before buying any new card, confirm the security architecture your system actually uses.

How the replacement works in FinanzOnline

1. Obtain the new card and check compatibility. Before changing provider, verify that your existing cash register supports the new unit.
2. Register the new signature or seal creation unit. The process requires details such as the type of security unit, trust-service provider and certificate serial number.
3. Take the old unit out of service. WKO refers to “Planmäßige Außerbetriebnahme” for a planned replacement.
4. Commission the new unit in the cash register. The technical steps depend on the cash-register provider.

If the same cash register continues unchanged, WKO says the register itself does not need to be deregistered and registered again. The relevant change is the assigned signature or seal creation unit.

Do you need a special DEP backup before the swap?

WKO’s current FAQ does not require a separate additional backup of the data collection log solely because of the card replacement. This does not remove the need for normal backup and record-retention practices.

A valid new card may still be incompatible with an old cash register

WKO warns that cash registers are not necessarily interoperable with cards from every trust-service provider. A legally valid card is therefore not automatically compatible with your existing system.

• Which software and cash-register version is installed?
• Which card generations does the provider support?
• Is a firmware or software update required?
• Does the card reader or other hardware need replacing?
• Who is responsible for registration and commissioning?

ACOS-ID 4.1 is now available

As of 24 September 2026, A-Trust lists RKSV products based on ACOS-ID 4.1 in its official web shop, with a stated certificate term of five years for the current product. Availability does not replace the compatibility check with your existing POS.

Replace only the card, or review the whole POS system?

If the current system is supported and the card replacement is straightforward, there is no reason to replace the whole POS solely because of this issue. But if the project also requires technician visits, hardware changes, software updates and substantial reconfiguration, compare the cost and operational risk of keeping the old setup with the cost of modernising it.

When reviewing a POS and checkout workflow, look beyond RKSV to receipts, daily closing, updates, hardware and support. Reporting and operational analysis can also show whether the existing system still gives management enough visibility.

If you switch systems, treat migration as a project

Products, tax rates, user roles, payments, receipts, hardware and reports should be validated before go-live. For older systems, data import and migration should be planned early rather than discovered after the new system has been purchased.

Practical checklist for the period to May 2027

• Identify whether your security unit is physical, online or HSM.
• If physical, record the exact SmartCard type.
• For ACOS-ID 2.1, schedule the replacement.
• For CardOS 5.3, confirm the provider’s timeline.
• Check compatibility before ordering.
• Assign responsibility for the FinanzOnline steps.
• Schedule the change well before the deadline.
• Test receipts and daily workflows after commissioning.

Where Lonio fits into the decision

If the swap is simple, the best approach is to complete it cleanly. If the exercise reveals that the existing system is becoming difficult to maintain across updates, reporting or hardware, it can be a sensible moment for a wider review. Use contact with Lonio to discuss requirements and whether a demo is relevant.

Conclusion

The key question is not “How old is my register?” but “Which signature-creation unit do I use?”. ACOS-ID 2.1 is directly affected, CardOS 5.3 should be planned for with May 2027 in mind, ACOS-ID 4.1 is not part of this specific replacement according to current WKO information, and online/HSM solutions follow a different architecture.

Note: This article reflects public information available on 24 September 2026 and is not binding legal or tax advice.

Official and technical sources

• BMF: RKSV signature-card certification information
• WKO: FAQ on affected RKSV cards
• WKO: replacement procedure
• A-Trust: ACOS-ID 4.1 RKSV product

A practical implementation timeline

A signature-card change looks small, but several dependencies sit behind it: the trust-service provider supplies the replacement, the cash-register provider confirms compatibility, someone needs the correct FinanzOnline access, and the business needs a low-risk moment to test the result. The safest approach is to work backwards from the deadline rather than treating May 2027 as the point to start.

1. Inventory the current setup

Record the cash-register model, software version, card type, provider and the identifiers your support team needs. If you operate several tills or locations, document whether they share one security setup or use separate units. This prevents one branch or legacy device from being missed later.

2. Get a compatibility confirmation

Before ordering, ask the cash-register provider which replacement card or security unit is supported by your exact version. Clarify whether a software or firmware update is required and whether the existing reader can remain in service. If a larger software upgrade is needed, schedule it before the card swap rather than discovering the dependency during implementation.

3. Prepare FinanzOnline responsibilities

Confirm who has the necessary access and who will perform the registration and decommissioning steps. If your tax adviser or external IT partner usually handles part of the process, agree the responsibilities and timing in advance. A missing login or unclear ownership on the change day is an avoidable operational problem.

4. Test the complete workflow after the swap

Do not stop at “the register starts”. Create a normal receipt, check the relevant security status, run a typical payment flow and complete the control steps your business normally uses at the end of a shift or day. The exact procedure depends on the system, but the goal is to discover problems before the next busy service period.

Common mistakes to avoid

• Ordering by card name alone: confirm compatibility with the exact software, hardware and reader first.
• Looking only at the age of the register: the installed security unit is the deciding factor.
• Treating the project as IT-only: FinanzOnline access, business timing and staff responsibilities also matter.
• Using the transition period as a reason to delay everything: support capacity, delivery times and older hardware can all create late surprises.
• Replacing the whole POS automatically: a supported system does not need to be discarded solely because of the card.

Decision matrix: card replacement or system replacement?

This is an operational decision aid, not a legal rule. The cheapest technical fix today is not always the lowest-cost path over several years, but the existence of a regulatory card change is also not, by itself, a reason to replace a functioning POS.

Questions to ask your cash-register provider

• Which signature card or security unit is currently active in our setup?
• Which replacement solution is supported by our exact software version?
• What update must be installed before the swap?
• Does the current card reader remain compatible?
• Which FinanzOnline steps does the provider handle and which remain with us?
• How should we verify the receipt and signature workflow after commissioning?
• What support is available if the change is scheduled outside business hours?

Use the deadline to clean up operational ownership

Even if you keep the existing system, the project is a useful reason to review logins, responsible people, device lists and documentation. Technical changes often fail because access credentials are outdated or nobody knows who owns a specific step. Cleaning up those basics during the signature-card project reduces risk for future software and hardware changes as well.

Frequently asked questions

Do all Austrian cash registers need a new signature card?

No. It depends on the signature or seal creation unit in use. Physical ACOS-ID 2.1 cards are affected; online and HSM solutions are not part of the physical card replacement.

Is May 2027 only the deadline for ordering a card?

No. Current BMF and WKO information says the card replacement and implementation must be completed by May 2027.

Does the cash register itself have to be registered again in FinanzOnline?

According to WKO, not if the same register continues unchanged. The new signature or seal creation unit is registered and the old unit is taken out of service.

Is ACOS-ID 4.1 affected?

According to current WKO information, not by this specific replacement. Compatibility should still be checked.

Is a special DEP backup required before swapping the card?

WKO does not list an additional dedicated backup of the data collection log as a required step solely because of the card swap.