50/30/20 Monthly Budget
Splits monthly net salary into 50% needs, 30% wants, 20% savings.
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The 50/30/20 monthly budget rule
Senator and bankruptcy law professor Elizabeth Warren laid this out in her 2005 book All Your Worth: The Ultimate Lifetime Money Plan. The idea is to take your net monthly income and sort it into three buckets. 50% needs are the things you can't easily drop: housing, food, utilities, transport, basic insurance. 30% wants cover dining out, streaming, leisure, the non-essential shopping. And 20% savings and debt repayment goes to your emergency fund, retirement contributions, and paying down anything beyond the minimum. So a net income of R$ 5,000 lands at R$ 2,500 for needs, R$ 1,500 for wants, and R$ 1,000 toward savings and debt. You skip the line-item spreadsheet and still get a quick read on whether things are healthy. Needs creeping past 50% means the structure is shaky, and savings stuck under 20% puts retirement in jeopardy.
Applications
You'll find it in financial-education courses aimed at young professionals and people in their first job. Apps like YNAB, Mobills, and Organizze lean on it as the default rule of thumb, and a lot of folks use it as a stepping stone before moving to zero-based budgeting. Couples reach for it to sort out shared expenses, and it's handy for figuring out why someone "earns well but never has money left".
FAQ
What if rent alone eats 50%? That's a sign you're overcommitted. You can move somewhere cheaper, find a way to earn more, or accept that your "wants" and savings get squeezed until the rent situation eases up.
Use gross or net income? Net, after IR and INSS. What matters is the money that actually shows up in your account.
Does it work on low incomes? Only up to a point. Once you're near minimum wage, fitting needs into 50% just doesn't add up. Run with 70/20/10 for now and shift back as your income climbs.
What about debt with high interest? Carrying a credit card balance or overdraft (rotativo)? Flip to 50/20/30 and hammer down the principal first. At 14%+ monthly interest, no investment is going to keep up.
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