I have various bills which come out throughout the month but on my current account spreadsheet I always show them as coming out on the 1st of the month so I know how much/little can be put aside and how much/little I have to live on for the rest of the month. It frequently means that what I have in my account and what my spreadsheet shows I have left don't match up until the 25th of the month when the last credit card payment is taken.
As a little bonus, I will be a bit better off next month as the last Cycle to Work payment was made from this month's salary alongside the second of two months without paying Council Tax.
We sort of do the same thing except we set up monzo to automatically split money for bills and spends.