This claim is false. Most of these hospitals are not “new”. More than half involve either rebuilding existing hospitals, replacing them, or building a hospital at a site that already exists.
Boris Johnson has repeatedly stated in the House of Commons and elsewhere that he is building 40 (or sometimes 48) new hospitals. The Prime Minister has repeated the false claim many times even though it has been repeatedly disproved by fact-check agencies and others, including this website. We are careful about using the term lie, but in this case, it is reasonable to call Johnson’s claim a lie (ie a statement made in the full knowledge that it is false and with the intention of misleading the listener).
For other examples of the Prime Minister making this false claim see here, here, here, here, here, here, here, here and here. Boris Johnson was lying in the House of Commons. According to the Ministerial Code, “It is of paramount importance that Ministers give accurate and truthful information to Parliament, correcting any inadvertent error at the earliest opportunity. Ministers who knowingly mislead Parliament will be expected to offer their resignation to the Prime Minister.”
We approached Mr Johnson’s office, the Cabinet Office and the No 10 Press Office to give them a chance to comment, but received no response.