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." Another way of explaining the puzzling balance: Right after a particular bill is paid, you have $0 saved to pay that bill the next time.  Just before the bill is next due, you wisely have the whole amount saved;  that's the purpose of the whole process.  So, for that bill, on average over time, you'll have one-half that upcoming bill in the account. But the same argument holds for every one of the upcoming bills.  So, for a large number of bills, with varying sizes and times between occurrence, the average amount in the account will be approximately one-half of the total amount of all the bills that you're saving for. "If you just had one expense once a year of $1200, you would put in $100 a month. The average balance is going to be $600 in that case - the 0 and $1200 months average to $600, as do the $100 and $1100, the $200 and $1000, and so on. If you had one expense twice a year of $600 and put in $100 per month it will average to $300. You have a mix of 3/6/12 months - does 8 months seem reasonable as an ""average"" frequency? If so, there should be about a 4 month slush all the time. Now instead of one expense averaged over 12 months, imagine 12 accounts, each needing $100 a month. If you started at zero, you would put in $1200 the first month and immediately spend it. One account would go from +100 (its share of what you put in) to -1100 while the rest are all at +100. Overall your balance would be zero. Then the next month you would again deposit 1200 and spend 1200, bringing one account to -1000, one to -1100, and the rest to +200. You average to zero actually on deposit because some of the ""accounts"" have negative balances and some have positive. But aren't doing that. You ""caught up"" the months you were  behind. So it would be like putting in $1200 for the first account, $1100 for the second, $1000 for the third and so on - a total of $7800. Then you take out $1200 and go down to 6600. The next month you put in $1200 and take out $1200 but you will always have that $6600 amount in there. All of the accounts will have positive balances - averaging $550 in this example." "It totally depends on when your expenses hit and whether you might have a larger stock than necessary. If you run your projections against the monthly save and the intervals of when you'll need the money, you might be able to extract some stock from the account.  I recommend making this a bit simpler. I operate this with an ""annuals"" account which is a complete aggregate of expenses that I know I have several times per year (or once every two years), but are not monthly or part of a weekly non-fixed expense budget cap. Instead of tracking each expense individually and saving for it, create a spreadsheet that lists out all of these expenses, sum them, and then divide by 12. When I first opened this account, I added a one-time deposit to ""catchup"" to make sure I would never need to pull money from another source for these expenses. As new expenses come into existence that I should plan for annually, I simply add them to this list and adjust the monthly auto-deposit to the account. This also adjusts my single number weekly budget.  To make it easy, whenever I see an expense on my annuals list on my amex or debit, I simply initiate a withdrawal from the annuals savings and it will balance out my weekly or monthly budget expenses.  The goal of my annuals account is to simply avoid anti-windfalls that are known quantities (insurance, annual eye exam, sprinkler flush, amazon prime, etc) that would throw a wrench in weekly/monthly budget and expense planning. The more variables you can remove from your weekly/monthly, the more regular it becomes and the more likely you will be able to stick to a budget."
Do you plan a monthly budget at the beginning of each month?  This might seem counter-intuitive, but hear me out. Doing a budget is, of course, critically important for those who struggle with having enough money to last the month.  Having this written spending plan allows people struggling with finances to control their spending and funnel money into debt reduction or saving goals.  However, budgeting can also help those with the opposite problem. There are some, like you perhaps, that have enough income and live frugally enough that they don't have to budget.  Their money comes in, and they spend so little that the bank account grows automatically.  It sounds like a good problem to have, but your finances are still out of control, just in a different way.  Perhaps you are underspending simply because you don't know if you will have enough money to last or not. By making a spending plan, you set aside money each month for various categories in three broad areas: Since you have plenty of money coming in, generously fund these spending categories.  As long as you have money in the categories when you go to the store, you can feel comfortable splurging a little, because you know that your other categories are funded and the money is there to pay those other bills.  Create other categories, such as technology or home improvement, and when you need an app or have a home improvement project, you can confidently spend this money, as it has already been allocated for those purposes. If you are new to budgeting, software such as YNAB can make it much easier. "I wrote a little program one time to try to do this.  I think I wrote it in Python or something. The idea was to have a list of ""projected expenses"" where each one would have things like the amount, the date of the next transaction, the frequency of the transaction, and so on.  The program would then simulate time, determining when the next transaction would be, updating balances, and so on.  You can actually do a very similar thing with a spreadsheet where you basically have a list of expenses that you manually paste in for each month in advance.  Simply keep a running balance of each row, and make sure you don't forget any transactions that should be happening. This works great for fixed expenses, or expenses that you know how much they are going to be for the next month.  If you don't know, you can estimate, for instance you can make an educated guess at how much your electric bill will be the next month (if you haven't gotten the bill yet) and you can estimate how much you will spend on fuel based on reviewing previous months and some idea of whether your usage will differ in the next month.  For variable expenses I would always err on the side of a larger amount than I expected to spend.  It isn't going to be possible to budget to the exact penny unless you lead a very simple life, but the extra you allocate is important to cushion unexpected and unavoidable overruns. Once you have this done for expenses against your bank account, you can see what your ""low water mark"" is for the month, or whatever time period you project out to.  If this is above your minimum, then you can see how much you can safely allocate to, e.g. paying off debt.  Throwing a credit card into the mix can make things a bit more predictable in the current month, especially for unpredictable amounts, but it is a bit more complicated as now you have a second account that you have to track that has to get deducted from your first account when it becomes due in the following month.  I am assuming a typical card where you have something like a 25 day grace period to pay without interest along with up to 30 days after the expense before the grace period starts, depending on the relationship between your cut-off date and when the actual expense occurs." Personally, I keep two regular checking accounts at different banks.  One gets a direct deposit totaling the sum of my regular monthly bills and a prorated provision for longer term regular bills like semi-annual car insurance premiums.  I leave a buffer in the account to account for the odd expensive electrical bill or rate increase or whatever.  One gets a direct deposit of the rest which I then allocate to savings and spending. It makes sense to me to separate off regular planned expenses (rent/mortgage, utility bills, insurance premiums) from spending money because it lets me put the basics of my life on autopilot.  An added benefit is I have a failover checking account in the event something happens to one of them.  I don't keep significant amounts of money in either account and don't give transfer access to the savings accounts that store the bulk of my money.  I wear a tinfoil hat when it comes to automatic bank transfers and account access... It doesn't make sense to me to keep deposits separate from spending, it makes less sense to me to spend off of a savings account. Paying yourself first involves getting some part of your income somewhat out of reach, with the intent that you don't spend it during the month.  It could be a retirement account, a savings account, or something similar. It's in contrast to saving whatever is left over at the end of the month: paying yourself last. The intent is to renormalize spending levels down, effectively living on a smaller income and saving or investing the difference.  The lower spending levels will become normal, and it won't feel quite as much like a belt-tightening exercise. The rule that I know is six months of income, stored in readily accessible savings (e.g. a savings or money market account).   Others have argued that it should be six months of expenses, which is of course easier to achieve.  I would recommend against that, partially because it is easier to achieve.  The other issue is that people are more prone to underestimate their expenses than their income.  Finally, if you base it on your current expenses, then budget for savings and have money left over, you often increase your expenses.  Sometimes obviously (e.g. a new car) and sometimes not (e.g. more restaurants or clubs).  Income increases are rarer and easier to see.   Either way, you can make that six months shorter or longer.  Six months is both feasible and capable of handling difficult emergencies.  Six years wouldn't be feasible.  One month wouldn't get you through a major emergency.   Examples of emergencies:   Your savings can be in any of multiple forms.  For example, someone was talking about buying real estate and renting it.  That's a form of savings, but it can be difficult to do withdrawals.  Stocks and bonds are better, but what if your emergency happens when the market is down?  Part of how emergency funds operate is that they are readily accessible.   Another issue is that a main goal of savings is to cover retirement.  So people put them in tax privileged retirement accounts.  The downside of that is that the money is not then available for emergencies without paying penalties.  You get benefits from retirement accounts but that's in exchange for limitations.   It's much easier to spend money than to save it.  There are many options and the world makes it easy to do.  Emergency funds make people really think about that portion of savings.  And thinking about saving before spending helps avoid situations where you shortchange savings.   Let's pretend that retirement accounts don't exist (perhaps they don't in your country).  Your savings is some mix of stocks and bonds.  You have a mortgaged house.  You've budgeted enough into stocks and bonds to cover retirement.  Now you have a major emergency.   As I understand your proposal, you would then take that money out of the stocks and bonds for retirement.  But then you no longer have enough for retirement.  Going forward, you will have to scrimp to get back on track.   An emergency fund says that you should do that scrimping early.  Because if you're used to spending any level of money, cutting that is painful.  But if you've only ever spent a certain level, not increasing it is much easier.  The longer you delay optional expenses, the less important they seem.   Scrimping beforehand also helps avoid the situation where the emergency happens at the end of your career.  It's one thing to scrimp for fifteen years at fifty.  What's your plan if you would have an emergency at sixty-five?  Or later?  Then you're reducing your living standard at retirement.   Now, maybe you save more than necessary.  It's not unknown.  But it's not typical either.  It is far more common to encounter someone who isn't saving enough than too much. One approach is to control your budget more effectively. For example work out your essential living expenses things like food, rent and other bills you are committed to and compare this to your regular income.  Then you can set up a regular automatic payment to a savings account so you limit the disposable income in your current account. If you keep a regular check on this balance it should make you feel like you have less 'spare' money and so less temptation to spend on impulse purchases.  Similarly   it may help to set a savings goal for something you really do want, even if this is itself  a bit frivolous it will at least help you to discipline yourself.  Equally it may be useful to set a fixed budget for luxuries, then you have a sense that when it's gone it's gone but you don't have to completely deny yourself. In general, the better advice I've heard is to spend only on things that matter to you and scrimp on the rest. It's an easy way to budget without having to stick to a strict set of rules. Otherwise keep 3-6 months of living expenses in liquid accounts (money market, savings) and invest the rest. I think JohnFx's answer is pretty much the right thing to do. I'd just like to suggest that the budget doesn't have to be fixed. It sounds like you aren't completely sure what an acceptable lifestyle costs for you, and it might feel like a budget locks you into a spending pattern that could end up being unfulfilling, or keep you in debt longer than necessary. To reduce that risk, you could start with a very easy level of contributions, then every month see if you can spend $10-$50 less without sacrificing in the lifestyle department. And eventually if you feel like you're missing out, you can stick with the previous month's budget. You might avoid depriving yourself by starting with something easy, but I think if you make an effort to save money, you'll more likely be surprised how much you can improve your lifestyle while spending less. I like a lot of the advice on Mr. Money Mustache and Early Retirement Extreme, and I'd recommend the introductory sections of both blogs if you ever hit a block at some level of contribution. And one minor (highly situational) comment: You mentioned having less to save if you contribute more, but if you have high interest loans, paying them down early can be (pretty much) a guaranteed very high ROI. So while you might want to prioritize an emergency fund and maybe an employer match first, most saving will probably be less useful than extra contributions. "If you are like most people, your timing is kind of awful.  What I mean by most, is all.  Psychologically we have strong tendencies to buy when the market is high and avoid buying when it is low.  One of the easiest to implement strategies to avoid this is Dollar Cost Averaging.  In most cases you are far better off making small investments regularly. Having said that, you may need to ""save"" a bit in order to make subsequent investments because of minimums.   For me there is also a positive psychological effect of putting money to work sooner and more often.  I find it enjoyable to purchase shares of a mutual fund or stock and the days that I do so are a bit better than the others.   An added benefit to doing regular investing is to have them be automated.  Many wealthy people describe this as a key to success as they can focused on the business of earning money in their chosen profession as opposed to investing money they have already earned.  Additionally the author of I will Teach You to be Rich cites this as a easy, free, and key step in building wealth." Emergency funds, by the name it implies that they should be available on hand at a very short notice if needed. Conservation of principal (not withstanding inflation, but rather in absolute terms) is also a very important criteria of any kind of account that you will use to save the emergency fund. I would suggest the following breakup. The number in brackets signifies the amount of per month expenses that you can keep in that account. = total 6 months living expenses "In many cases the expenses are not pulled out on a specific day, so this wouldn't work. On the other hand some funds do charge an annual or quarterly fee if your investment in the fund is larger than the minimum but lower than a ""small balance"" value. Many funds will reduce or eliminate this fee if you signup for electronic forms or other electronic services. Some will also eliminate the fee if the total investment in all your funds is above a certain level. For retirement funds what you suggest could be made more complex because of annual limits. Though if you were below the limits you could decide to add the extra funds to cover those expenses as the end of the year approached." You need to know loans are not free; and they are not a way to solve budget issues. If you are having problems with making your income last over your expenses, you do not need to add another expense (in the form of a loan) What you really need to do is create a budget, track and understand your expenses, and then decide if you should focus on raising  your net income level or cutting down expenses. Keep up with your budget.  You can reduce the frequency, but you need to track your spending really for the rest of you life.  It is just a good habit, like personal hygiene. Once you understand your money (via your budget), you can start to save money into an emergency fund that will cover you during the times of zig zags. I say it very plainly as if it is super easy; but it requires will power and the foresight to understand that if you don't manage your money, nobody else will.  Being sane with your money is one of the most important things you can do now to improve your future. IMPROVEMENT NathanL has an excellent first step with budgeting:  Allocate money to be spent for the next month from money made during   the previous month. This will build a cushion into your budget and   alleviate the fear that the OP mentioned More moving parts will make your budget harder to keep track of, not simpler. Budget systems like You Need a Budget recommend simplifying your accounts, even if the various accounts give you specialized bonuses like rewards for restaurants or gasoline or travel. The effort of keeping track of all the options and accounts can outweigh the value you get from them. Instead, I recommend using a simple and structured budget system (like YNAB) that walks you through all of the steps toward building good habits and keeping them simple so that you can maintain the habit. One situation where it would be prudent not to contribute would be if expenses are so tight that you cannot afford to contribute because you need that cashflow for expenses. Assuming what is taking you over budget are not essential costs such as fuel bills, food, mortgage etc. you could do the following. Work out your monthly disposable income after all essential base costs have been sutracted. Then simply keep a book of any additional spending.  It will be very easy to see if you're at risk of overspending. In fact, even when one has no need to budget it's still an excellent idea to keep a book of all your spending. It's surprising how useful it can be. It's a great reference for dues dates, sizes of past bills and provides an excellent cross check of your bank statement. It's not often that you find an error on your bank statement (at least it shouldn't be!), but my books have helped me locate three such errors over the past 25 years, which I'm sure would have gone unnoticed by most people. So my advice is, keep a book of your spending.