SONIA sterling overnight index average

Source: Bank of England Statistical Database, series IUDSOIA (SONIA). Licence: SONIA data licensed under the Open Government Licence v3.0 and copyright the Governor and Company of the Bank of England. The trade marks “Bank of England” and “SONIA” are registered trade marks of the Bank of England (terms). Files: data/raw/boe-sonia.csv.

Reading this series

SONIA is the sterling overnight index average, the risk-free reference rate for sterling and the benchmark that replaced LIBOR in that role. The Bank of England publishes it from transaction data, but it does not set it: it is a market rate reflecting unsecured overnight borrowing. This page uses Bank of England series IUDSOIA, under the Open Government Licence, with history from 1997 that includes the 2018 reform of the benchmark.

Because it is a market rate, SONIA moves daily and is not stepped. The headline is the latest daily print; the chart and the long-run statistics use month-ends, which keeps the drawn series readable. Read the value with its as-of date, then the "versus the previous reading" line for the most recent change. Mean, median, low and high summarise the observations in this build, not an official average. Chart and Table present one series two ways, range buttons filter the window, and Explore loads zoom and pan only when asked. SONIA is not Bank Rate, and it is not a mortgage or savings rate.

About this desk

The euro-area desk is the natural home for the two shared ECB series: the deposit facility rate, which is the euro-area policy rate set by the Governing Council, and €STR, the unsecured overnight market benchmark the ECB publishes but does not set. The Germany, France, Italy and Ireland desks point at the same two series; this desk presents them without a single country's framing.

The figures come from the ECB Data Portal and are republished with attribution under the ESCB statistics reuse policy. All desks show the same build-wide series in a different order, so the numbers here match the country desks exactly. The build does not include national retail or mortgage rates for euro-area members, because none is ingested. Euro-area policy is one setting for all members; the site does not invent a national rate. This is not financial advice.