Emergency fund

Funds set aside for unexpected expenses and kept separate from retirement or other investments. The quantity of emergency funds is usually specified as an integer multiple of monthly expenses, e.g., Six months to one year's worth of expenses. Emergency funds should be invested in a highly liquid, low risk vehicle (e.g., money market, bank savings account).

The goal of the emergency fund is to provide a cushion of liquidity in the event of unexpected expenses.

It is generally best to establish a modest emergency fund and pay down high-interest-rate debt (such as credit card debt) before investing in equities. The emergency fund provides security against having to sell equities during down markets, since most true investment assets are best held for the long term.

Multi-tiered Emergency Fund
By far the most common emergency that would require dipping into the emergency fund is the loss of a job. Since in such a scenario you will not need all the funds at once, some investors seek to have multiple tiers of emergency fund so that funds not needed for several months can be placed in short-term bonds (including CDs) to earn higher yield.

Those investment products include very short-term Treasury bills, as well as CDs (which often have embedded options which allow them to be cashed in at any time for a small penalty). I Bonds, which after some period can be cashed in at no cost, can also form a part of this second tier of emergency fund.

For instance, a multi-tiered emergency fund could consist of: 1. Three months of expenses in cash (bank account or money market fund) 2. The next three months of expenses in CDs with the option to cash them in for three months of interest 3. The next three months of expenses in a short-term Treasury bond fund. Selling these would risk incurring some loss of principal due to interest rate changes, but since the odds of needing to rely on your emergency fund for more than six months are slim, some would consider this an acceptable compromise.

Cash Emergency Fund vs Line of Credit
Some people view various forms of credit (particularly HELOCs ) as suitable for emergency funds; others strongly disagree. Credit lines can often be withdrawn with little or no notice, and some emergencies which require drawing on the emergency fund may also cause a creditor to question your ability to repay.

Roth IRA as an emergency fund
In some situations, a Roth IRA can be used as emergency fund. From IRS Publication 590:

"Withdrawals of contributions by due date. If you withdraw contributions (including any net earnings on the contributions) by the due date of your return for the year in which you made the contribution, the contributions are treated as if you never made them. If you have an extension of time to file your return, you can withdraw the contributions and earnings by the extended due date. The withdrawal of contributions is tax free, but you must include the earnings on the contributions in income for the year in which you made the contributions."

Only withdrawals from Roth IRA contributions can be used without penalty. Distributions must be qualified to avoid penalties.

A Roth IRA is primarily intended for retirement, not to store emergency funds. One should consider the impact to portfolio allocations and potential custodial costs. There are behavioral considerations, as well. If a choice is to be made between funding a Roth IRA and an emergency fund, a Roth IRA can be used as an emergency fund in the appropriate situation.