A saving formula is wording in a notice (normally a section 21 or notice to quit) which provides a fall back date in the event of any written date within the notice being wrong. It is used when the date of expiry must be precise such as if the notice must expire on the last day of a period of the tenancy. The use of saving formulas has been long approved including in particular Elias v Spencer  EWCA Civ 246. See our saving formulas in notices article for more information.
In Spencer v Taylor  EWCA Civ 1600 a section 21 notice was served which contained a date and a saving formula. It was suggested that in order for this combination to be acceptable, the dates and formula might need to be clearer than first thought.
In Spencer, the section 21 notice said:
[.. The landlord ..] required possession of the dwelling house, [.. address ..]
(a) after 01/01/2012
Or (b) at the end of your period of tenancy which will end next after the expiration of two months from the service upon you of this notice.
This type of date followed by a formula was held to be valid despite it not being relevant to the case (in this case, it had already been decided that the notice was valid without the need for the formula.)
Regrading this combination of date and formula, the court said (highlights added by author):
The perceived problem in our case is that the notice contains both a fixed date and also a formula, the application of which results in a different date from the fixed date. The first point that Mr Colville takes is that this very fact invalidates the notice. Section 21(4) requires that the notice specifies “a date.” That means only one date and if a notice specifies two dates that very fact invalidates it.
But that in my judgment must depend on the way in which the two dates are expressed to operate. If the reasonable reader of a notice would understand that one date is the primary date and the other date is a fall back then I can see no reason to invalidate the notice on that account. Mr Colville accepted that if the notice makes this clear then it will be valid. …
Then at the bottom of the judgment, it is further confirmed:
In order to see whether the notice complies with the statutory requirement, one must see what it does. In our case the notice refers to two dates, the fixed date and the date calculated by reference to the formula. They are clearly alternatives, as the word “or” separating them makes clear, so they are at least capable of leading to different results. In the event that they do, which one prevails?
In my judgment, the reasonable recipient of this notice would look at the back of the form which contains the notes and they say that the notice must specify the last day of a period of the tenancy. She would know that she paid her rent on the Monday and she would be able to see from the calendar that 1 January 2012 was a Saturday. So it obviously was not the last day of a period of the tenancy. Conformably with Fernandez v McDonald, that mistake, if such it was, cannot be corrected. But that leads to the conclusion that that part of the notice does not do what the notes on the back say it must do. So that part of the notice cannot be effective. Since that alternative is ruled out as being ineffective, the other alternative must prevail.
But previously there was a warning:
If both dates satisfy the requirements of section 21(4) and there are simply no means of knowing which is to take priority, there may be a problem. Judge Godsmark thought that there would be and he may well be right. But that is not our case and can wait for a case in which it matters.
Landlords should therefore remain careful when using notices which contain both a date and a saving formula. Ensure that it is clear which date is primary and which date is a fall back position. It would seem giving both date and formula equal weight could potentially cause a problem.  Copying the above example or using just a formula (which the Guild notices use) is our advice.
- Although here the judgment refers to the date and formula both being the same which seems strange as to how that could cause a problem? ↩