I can hear the claims of “Heresy!” ringing out through the personal finance world right now. How can I say the 3 to 6 month emergency fund rule is stupid?! Before you give yourself a heart attack, you need to realize that I’m not saying an emergency fund is stupid. Not by any means! In fact, I’ve written several times already about why you need an emergency fund, where to keep your emergency fund, when you should use your emergency fund, and how to build up your emergency fund. Clearly, I have nothing against emergency funds.

       No, my problem is with the silly rules of thumb that get thrown around with the idea of the emergency fund. Some say you need 3 months of your expenses, some say 6, and some say 9. I’ve even heard 2 years! The problem is that all these simple rules of thumb make the same mistake that other rules of thumb make – they ignore your circumstances.

Base Your Emergency Fund on Your Circumstances

       An emergency fund based on 3 months of your living expenses may work fine if you’re married and both of you have stable jobs with comparable incomes and you have your finances under control. But change just one of those variables (marital status, job stability, income disparity, or financial situation) and you can forget about a 3 month emergency fund doing the job.

       The size of your emergency fund needs to be tailored to your circumstances because the riskiness of your situation is determined by what’s happening in your life – not what some rule of thumb tells you. Now, I’ll grant that a 6 to 12 month emergency fund is going to be in the right zone for most people, but I wouldn’t leave this to a guess. You need to take a few minutes to think about your situation and adjust accordingly.

       For example, if you’re single then you probably only have one source of income. That puts you at a higher risk in case of a job loss than someone who is in a two-income household. The same goes for your job stability. If there’s little risk you’ll lose your job (maybe a government position?), then you’re probably a bit safer than someone in a cyclical industry (car sales, perhaps).

       If you’re socking away 20% of your income, a small emergency might not bother you too much. You can easily divert your money away from saving for a bit and go back after the emergency has been covered. But if you’re struggling to make it from one paycheck to the next, even a small $100 car repair can throw your whole world into a giant mess.

       It’s these kinds of factors that should determine how much you need in an emergency fund. I’ve talked about how much you need in an emergency fund, so I’m not going to go over it again. But keep in mind that even my article is just a general guideline. You’ll still need to think critically about your specific needs and situation.

Beware Rules of Thumb

       I’ve written several of these types of articles over the last few months. I talked about the stupidity of the save 10% for retirement rule, the 2.5 or 3 times your income for a mortgage rule, and the 80% or 90% of your income for retirement rule.

       All of these rules are guilty of oversimplification, a complete ignorance of your unique circumstances, or both. Yet some people rely on these rules of thumb for their most important financial decisions. I’m not saying you need a financial planner. But please do yourself a huge favor and take some time to think about your situation and what makes sense for you. Don’t rely on stupid rules of thumb to determine your financial future!

Any Other Rules of Thumb?

       What financial rules of thumb have you heard of that you’d like to learn more about? Are there any you question but aren’t sure why they might be wrong? Let me know in the comments below and I’ll be happy to write an article specifically tailored to answer your questions!

(photo credit: Alan Cleaver on Flickr)

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