I want to subtract a value in a cell with a set value on the same date each month? Is this possible?

How can I subtract a value in a cell with a set value on the same date each month?

I have set the date on my spreadsheet but can I use it to subtract a value from a cell value?

Please provide an example - I can not understand what you want to achieve.

Same date each month, would it be the day?

In one cell I have the value £5318, I want to create a formula that reduces this value by £100 on the 25th of every month. Is this possible? If so, what would be the formula please?

It is still not clear, what you want to achieve. For sure you can subtract 100 from 5318 on a 25th day of a month (see 1st Answer below). But what should happen on and after 25th of 2nd months, 25th of 3rd months and so on… Do you want it to show

25th of 1st month: 5318 - 100
25th of 2nd month: 5318 - 100*2
25th of 3nd month: 5318 - 100*3
... an so on

?
What should it show after the 25th of the 1st month: Back again 5318 or keep 5318-100 until 25th of next month. (Proposals/Solutions require a clear definition of the problem)

Sorry, newbee here, so pardon me for the basic clarification:
The question was clearly answered, should we dwell in what happens next or will we go off-topic?

@wizaxx sorry - but as my additional comment should make clear, your answer is an answer to an undefined problem and the answer doesn’t address the phrase every month. In that sense your answer is clear answer to the question How to show 5318 - 100 on 25th of a month, and 5138 the rest of the days? which I suppose isn’t OPs question.

sorry again for the newbee status: I didn’t assume or suppose, I just answered a very clearly posed question with a direct solution (on the same date, each month, it subtracts a value in a cell with a set value) - although, like you, I wonder what’s next, but isn’t this a different topic?

Sometimes opinions differ and mine is that your answer is based on assumptions and the question isn’t clear. But it is not on me to decide whether your answer satisfies OPs requirements. OP decides.

I am so glad we have this friendly exchange at my very fist interaction, “I want to subtract a value in a cell with a set value on the same date each month? Is this possible?” is a very clear question and I made no assumptions. It would be different to assume OP meant to ask something else… and Yes I give up , as it seems a mute issue now.

If I understand correctly you have a cell with a value (5813) and you would like to remove some value (100) on a specific date of the month (the 25th).
So you would have:
5831 in cell A1
100 in cell A2
and want cell A3 to calculate =A1-A2 only on the 25th of each month.

If that’s correct the solution is to know today’s date, check if in is the 25th and if so calculate =A1-A2.
Fortunately it is possible using a combination of the built in functions TODAY() and DAY().

Enter this formula in Cell A3: =IF(DAY(TODAY())=25,A1-A2,A1)

Now I am sure you are aware that on the 26th the value of A3 will go back to the original value (5813) unless you capture it… but that’s another topic

I hope this helps.
best regards,
mZ