Offer your thoughts or opinion on the input financial query or topic using your financial background.

Why does it seem unnecessary to fully save for irregular periodic expenses?
I think we'd need to look at actual numbers to see where you're running into trouble. I'm also a little confused by your use of the term "unexpected expenses". You seem to be using that to describe expenses that are quite regular, that occur every X months, and so are totally expected. But assuming this is just some clumsy wording ... Here's the thing: Start out by taking the amount of each expense, divided by the number of months between occurrences. This is the monthly cost of each expense. Add all these up. This is the amount that you should be setting aside every month for these expenses, once you get a "base amount" set up. So to take a simple example: Say you have to pay property taxes of $1200 twice a year. So that's $1200 every 6 months = $200 per month. Also say you have to pay a water bill once every 3 months that's typically $90. So $90 divided by 3 = $30. Assuming that was it, in the long term you'd need to put aside $230 per month to stay even. I say "in the long term" because when you're just starting, you need to put aside an amount sufficient that your balance won't fall below zero. The easiest way to do this is to just set up a chart where you start from zero and add (in this example) $230 each month, and then subtract the amount of the bills when they will hit. Do this for some reasonable time in the future, say one year. Find the biggest negative balance. If you can add this amount to get started, you'll be safe. If not, add this amount divided by the number of months from now until it occurs and make that a temporary addition to your deposits. Check if you now are safely always positive. If not, repeat the process for the next biggest negative. For example, let's say the property tax bills are April and October and the water bills are February, May, August, and November. Then your chart would look like this: The biggest negative is -370 in April. So you have to add $370 in the first 4 months, or $92.50 per month. Let's say $93. That would give: Now you stay at least barely above water for the whole year. You could extend the chart our further, but odds are the exact numbers will change next year and you'll have to recalculate anyway. The more irregular the expenses, the more you  will build up just before the big expense hits. But that's the whole point of saving for these, right? If a $1200 bill is coming next week and you don't have close to $1200 saved up in the account, where is the money coming from? If you have enough spare cash that you can just take the $1200 out of what you would have spent on lunch tomorrow, then you don't need this sort of account.