To ask the Chancellor of the Duchy of Lancaster and Minister for the Cabinet Office, with reference to his Department's press release, Government’s streamlined messaging service to save taxpayer £175m, published on 26 September 2019, what the sources are of the savings that the GOV.UK Notify system will deliver in each of the next five years.

GOV.UK Notify currently has 1,322 services with over half a billion total notifications sent to date (see here). The benefits of GOV.UK Notify are primarily driven by HMG only having to incur a cost once instead of multiple times across the 1,322 services. The benefits fall into two broad categories "One-off avoided costs" & "Avoided ongoing costs". These benefits are driven by the number of services adopted across HMG and the transactions of each of those services. Both are forecasted forward based on a combination of statistical techniques using historical data and engagement insight with OGDs.