The Test of Confidence:  An Interrupted Time Series Analysis of the Liquidity Effects of the VIBER ISO 20022 Migration

Authors

DOI:

https://doi.org/10.35551/PFQ_2026_3_3

Keywords:

Time Series Analysis, large-value payment systems (LVPS), electronic payments, introduction VIBER ISO 20022 migration, liquidity management, C22, E42, E44, E58

Abstract

This study examines the liquidity effects of the migration of the Hungarian Real-Time Gross Settlement (RTGS) system (VIBER) operated by the Central Bank of Hungary (MNB) to the ISO 20022 messaging standard. The objective is to determine whether the 27 October 2025 go-live resulted in a detectable structural break or a persistent change in the trend of VIBER’s aggregate closing balance. The empirical analysis is based on interrupted time series (ITS) segmented regression, complemented by robustness checks using ARIMA models. The initial regression results indicated a temporary decline in balances and a post-migration change in trend. However, after controlling for VAT payment periods, the temporary effect was no longer statistically significant. In the ARIMA models accounting for the autoregressive structure of the time series, neither the shock associated with the migration nor the post-migration change in trend proved robust. The findings suggest that a substantial proportion of the observed balance movements can be explained by the internal dynamics of the time series and by liquidity reallocations associated with tax payment periods. Interviews conducted with bank liquidity management specialist further confirmed that the migration did not require any extraordinary liquidity-management adjustments. Overall, the results indicate that the VIBER ISO 20022 migration was implemented without significant liquidity disruptions, which points to the successful preparation of project and to the high level of market confidence in the central bank.

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Published

2026-09-29

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Section

Studies

How to Cite

Taczmann, R., Tóth, F., & Varga, L. (2026). The Test of Confidence:  An Interrupted Time Series Analysis of the Liquidity Effects of the VIBER ISO 20022 Migration. Public Finance Quarterly, 72(3), 52-79. https://doi.org/10.35551/PFQ_2026_3_3