One piece of standard advice that I just hate is that you should keep an emergency fund of three to six months worth of expenses. I personally don’t have one, instead I keep a unused line of credit that can cover about five months of expenses.
Why do I avoid an emergency fund? I plan for an entire year’s worth of normal expenses in advance, so having the car insurance or Christmas come due is hardly a surprise. I save a set amount each month into my high interest savings account and pull out the money for those yearly expenses when the come up. That way I’m not having too large of a sum of money sitting around, uninvested and losing its value to inflation but I do have a large enough fund to help cushion those unexpected expenses.
As for a true emergency, I have used the line of credit before and found it worked out fine. After our baby was born ten weeks early, we had a lot of unexpected expenses (hotels, food) including the replacement of one of the main structural beams in our house for $9,000 and the car lease buyout for $8,000 (the story on the lease is an entirely new post). The total damage was about $22,000 in three months. So after maxing out the line of credit and stripping down every penny I had saved in non taxable accounts I was still $5000 short. So I took an offer of help from my parents and took out a loan from them for $5000 to be paid back in 8 months.
In 12 months I had manged to pay off the entire debt, which given the size of the emergency I feel is a perfectly acceptable time frame. So depending on your own situation, you may be better off with a $0 emergency fund.