Iceland is a payments paradox. The country is one of the most cashless societies on earth - only 2-3% of transactions use physical currency - yet more than 90% of its retail card payments are processed abroad by Visa and Mastercard through just four submarine data cables. The Central Bank of Iceland (Sedlabanki) operates a sophisticated interbank payment system that can handle 5 million transactions per day, but the island's geographic isolation creates a unique resilience challenge that no other Nordic country faces at the same scale.

MBK - The Interbank Payment System

The CBI's MBK (MilliBankagreidsluKerfid) is the core of Iceland's payment infrastructure. Launched on 26 November 2020, it replaced the legacy SG (large-value) and JK (instant) systems that had operated since 2002 and 2003 respectively.

Architecture: MBK consists of three integrated components: RTGS - Real-Time Gross Settlement for high-value payments EXP - Instant/fast payment component for retail payments (accessible 24/7/365) PAYHUB - Routing and integration hub that transforms proprietary messaging into ISO 20022-compatible formats

Technology: Built by SIA (now part of Nexi Group) using a commercial off-the-shelf platform. Implementation took approximately three years.

Capacity: Designed to handle up to 5 million payments per day, with each transaction processed in under 40 milliseconds. Current throughput reaches up to 1 million payments per day with peaks of 160,000 transactions per hour. For a country of approximately 365,000 people, this implies roughly 2.7 payments per person per day at peak capacity.

Participants: 9 domestic banks, including the three major commercial banks (Landsbankinn, Islandsbanki, Arion Banki) plus Kvika Bank and others.

Currency: Icelandic krona (ISK) only.

RTGS Component

The RTGS component settles high-value payments individually in central bank money at the CBI, with gross settlement finality.

Legacy context: The predecessor SG system handled only transactions of ISK 10 million or more during banking hours (09:00-16:30). The new RTGS component within MBK has no such restrictions on availability within its operating window.

EXP - Instant Payments

EXP is Iceland's fast payment system, integrated into MBK.

Settlement model: Deferred Net Settlement (DNS) - clearing happens within EXP and net positions are settled in the RTGS component. Although settlement is deferred, end-users receive funds instantly.

Availability: 24/7/365. This is a significant improvement over the legacy JK system, though both provided real-time user experience.

Messaging: Based on ISO 20022 internally, though participants communicate with MBK using a proprietary format that PAYHUB transforms, minimising the implementation burden on banks.

Historic note: Iceland has operated real-time interbank payments since 1985 - one of the earliest implementations globally. The JK instant payment system launched in 2003 was already available around the clock for transactions under ISK 10 million.

Greidsluveitan - Clearing and Infrastructure Operator

Greidsluveitan ehf. is a private limited company wholly owned by the Central Bank of Iceland that operates the country's core payment infrastructure. It describes itself as "the centre of the country's financial infrastructure."

Systems operated: Netting System - multilateral netting of retail payments between banking institutions, with net amounts settled in gross settlement accounts at the CBI twice per business day Card Payment Switching System - centralised domestic card transaction processing SWIFT Services - international fund transfer management Collections System - electronic claims and remittance documentation Digital Document Delivery - processing more than 2 million new e-documents per month across 3,000+ organisations

Volumes: The netting system processes approximately 68 million transactions totalling over ISK 4 trillion annually.

RB (Reiknistofa bankanna) - Technical Operator

RB, the Computing Centre of the Banks, is a non-profit cooperative founded in 1973 and jointly owned by Iceland's three main banks, two savings banks, the Icelandic Savings Bank Association, and three payment card processors. With approximately 149 employees, RB has developed and operated all main financial systems and payment solutions in Iceland for over 40 years.

Role: RB provides core banking solutions (multi-tenant, used by all Icelandic banks including the CBI), technical operations for MBK, e-invoicing and e-payment systems, and cybersecurity operations. RB operates across two data centres.

SEPA and EEA Status

Iceland is an EEA member state through EFTA, placing it within the geographical scope of SEPA. Icelandic banks can participate in SEPA Credit Transfer (SCT) and SEPA Direct Debit (SDD) schemes for euro-denominated payments. SEPA Instant Credit Transfer (SCT Inst) does not appear to be available through Icelandic PSPs currently.

The critical distinction: SEPA covers only euro-denominated payments. Since Iceland uses the ISK domestically with no plans to adopt the euro, SEPA applies exclusively to cross-border EUR transactions. All domestic ISK payments flow through MBK and Greidsluveitan.

T2 and TIPS Feasibility Assessment

In September 2024, the ECB welcomed the CBI's decision to begin a feasibility assessment for joining the Eurosystem's T2 (RTGS) and TIPS (instant payment settlement) infrastructure. The assessment focuses on TIPS first, then T2.

If implemented, Icelandic market participants would be able to settle payments in central bank money in both EUR and ISK through Eurosystem infrastructure. This would make Iceland the second non-euro currency on TARGET, following Denmark's DKK migration in April 2025.

No completion date has been announced. The CBI is evaluating technological, operational, statutory, and security requirements through stakeholder working groups.

The Domestic Card Processing Initiative

This is Iceland's most distinctive payment infrastructure challenge. Currently, over 90% of all retail card payments are routed through Visa and Mastercard processing centres abroad. Iceland is connected to other countries by only four submarine data cables. If those cables were severed - whether by natural disaster, cyberattack, or geopolitical disruption - the vast majority of domestic retail payments would stop working.

In January 2025, Bloomberg reported that Greidsluveitan is leading an initiative to build domestic card payment processing capability. The goal is to ensure that transactions between Icelandic cardholders and Icelandic merchants can be processed entirely within the country, without depending on overseas infrastructure.

Greidsluveitan's CEO indicated the solution could be operational within 2025. The IMF's 2025 Article IV mission to Iceland explicitly welcomed authorities' efforts to enhance the resilience of the domestic payment system in the face of growing cybersecurity threats.

What Practitioners Should Know

Iceland's payment infrastructure is remarkably sophisticated for a market with four commercial banks and 365,000 inhabitants. The MBK system's capacity of 5 million payments per day - roughly 14 per person per day - reflects significant overengineering for resilience.

The key vulnerability is the dependence on foreign card processing infrastructure. While MBK and Greidsluveitan handle interbank and netting operations domestically, the card payments that dominate retail commerce flow through submarine cables to overseas processing centres. The domestic processing initiative is designed to close this gap.

For institutions routing payments to Iceland: ISK interbank payments flow through MBK (RTGS for high-value, EXP for instant). Euro-denominated SEPA transfers are available through Icelandic banks' SEPA participation. Card payments denominate in ISK but currently process offshore.

The T2/TIPS feasibility assessment is worth monitoring. If Iceland connects to TIPS, it would gain access to the eurozone's instant payment settlement infrastructure for EUR payments, potentially reducing costs and improving speed for cross-border euro transactions.

Payment transmission costs in Iceland are notably high at 1.25% of GDP (2023), compared to approximately 0.93% in Sweden and 0.79% in Norway. The small market size and reliance on international card scheme processing contribute to these elevated costs.

Sources: Central Bank of Iceland - Interbank Payment System; World Bank FASTT - EXP Case Study (Iceland); ECB - Sedlabanki Islands Expresses Interest in T2 and TIPS (September 2024); Bloomberg/BNN - Cyber Threats Spark Iceland Plan to Process Payments at Home (January 2025); Greidsluveitan - About; IMF - Iceland 2025 Article IV Staff Concluding Statement (May 2025).