The 50/30/20 budget, explained

The 50/30/20 budget splits your take-home pay into three buckets: half for things you must pay, 30% for things you want, and 20% for savings and debt payoff. It is popular because you only have to track three numbers. Here is where the rule comes from, how to set it up, and when it needs adjusting.

Where the rule comes from

The split is usually credited to Elizabeth Warren and her co-author, Amelia Warren Tyagi. They laid it out in their book All Your Worth: The Ultimate Lifetime Money Plan, published by Free Press in March 2005. The book's description divides your money into "Must-Haves," "Wants" and savings.

In a 2005 Money magazine interview, the authors described their "Balanced Money Formula" as dividing take-home pay into three parts: about 50% for must-haves, 30% for wants and 20% for savings, with paying off debt counted in the savings share. A CBS News report from March 2005 summarized the same split as "roughly 50 percent (must-haves), 20 percent (savings), 30 percent (wants)."

The word "roughly" matters. The authors offered targets to aim for, not exact limits.

The three buckets

A simple test for must-haves: would you still have to pay it if you lost your income next month? Rent, insurance premiums and minimum loan payments usually pass that test. A gym membership or a premium phone plan usually doesn't, even if it feels essential.

In the Money interview, the authors pointed to housing, cars, preschool, child care and health care as basics whose costs have grown for families. Warren's reasoning was that the formula is safe: with must-haves near half your pay, you can more easily get by on one income or an unemployment check if you lose a job.

How to apply it to your take-home pay

1. Find your monthly take-home pay. Use the amount that actually lands in your account. If you're paid every two weeks, add up a few months of deposits and divide by the number of months for a fair average.
2. Multiply by 0.5, 0.3 and 0.2. These are your three targets.
3. Sort last month's spending into the three buckets. Use your bank and card statements, not memory.
4. Compare your real numbers with the targets. The gaps show you where to focus.

For example, if you take home $4,000 a month, the targets are:

If your must-haves come to $2,300, you are $300 over. You could cover that by cutting wants to $900 for now, or by looking at whether a fixed cost such as insurance or a phone plan can come down.

One judgment call: if your employer already takes retirement contributions out before your paycheck, that money never shows up in your take-home pay. Some people add it back and count it toward the 20%. Others leave it out and use the 20% for other savings and debt. Either approach works as long as you know which one you are using.

When 50/30/20 doesn't fit

High housing costs

Where rents are high, housing alone can take a large share of a paycheck. An article from HUD's Office of Policy Development and Research notes that the Department of Housing and Urban Development defines cost-burdened families as those paying more than 30% of their income for housing, and describes severe rent burden as paying more than 50% of income on rent. If housing is already near half of your take-home pay, the 50% must-haves target will be hard to hit, whatever you do with groceries or utilities.

In that case, a split like 60/20/20 or 65/15/20 may be more honest for now. Protecting the savings share usually matters more than protecting the wants share, because savings is what absorbs the next surprise bill.

Debt

The original formula puts debt payoff inside the 20%. If you have high-interest credit card balances, the full 20% may need to go to debt for a while, which leaves little for savings. The authors argued in the Money interview that holding savings while carrying credit card debt works against you. Even so, keeping a small cash cushion can stop the next surprise expense from going straight back on the card.

If your required minimum payments alone push must-haves well past 50%, that is useful information. It may be a sign to look at the debt itself, such as which balance costs the most in interest, rather than squeezing every other category.

Irregular income

If your pay changes month to month, the percentages move with it. A budget built on your lowest typical month, with extra income set aside when it arrives, is often easier to keep than a fixed split. A zero-based budget, where you assign every dollar each time you're paid, can be a better fit for freelancers and gig workers.

Already ahead

If your must-haves are well under 50%, you don't have to fill the gap with wants. Moving some of that room into savings is how the 50/30/20 split can become something like 45/25/30 over time.

Making the split stick

• Automate the 20%. Schedule a transfer to savings or an extra debt payment for the day after payday, so it happens before spending does.
• Review monthly. Compare each bucket against its target once a month and adjust. A single expensive month is not a failed budget.
• Recalculate when your pay changes. A raise, a new job or a move changes all three targets.

How SpendySaver helps

SpendySaver's Budget includes a 50/30/20 template you can use as a starting point for your category budgets. If you would rather start from real numbers, "Suggest my budget" builds a starting budget from your last three months of spending, and you can then adjust your category amounts to fit your costs.