How can I create a family budget I can actually stick to?

What are the four steps?

Banco de Portugal suggests these steps, at the start of each month:

1. List the net income you receive. Count only certain income, such as a salary or pension.
2. Record the costs you expect for the month.
3. Work out the balance: income minus costs.
4. Decide how much you want to save, and for what.

Also draw up a yearly budget, for costs that come once a year, such as insurance.

How do I sort my costs?

• Necessary: food, housing, health and education. You can reduce them, but not remove them.
• Non-essential: travel, leisure and restaurants. You can cut them if needed.
• Fixed: they do not change from month to month, such as your mortgage repayment.
• Variable: they depend on use, such as water, electricity and gas.

The more your fixed costs weigh, the harder it is to face something unexpected.

What if my income changes every month?

Use the monthly average of the last year. Do not count bonuses, commissions or inheritances you are not sure to receive.

Review your budget whenever your income or costs change.

How much should I save?

Todos Contam gives an example: 10% of your income, or 20% for a more ambitious goal. On €2,000 a month, that is €200 or €400.

Set that amount aside at the start of the month. Saving is not what is left at the end.

What about the 50/30/20 rule?

It is a rule of thumb, not an official one: 50% for needs, 30% for the rest and 20% for savings. It can be a starting point. Your real budget is what counts.

An example with the sums

You earn €2,000 net a month. Your fixed costs are €1,100, including a €600 mortgage repayment. Variable costs come to €500.

The balance is 2,000 − 1,100 − 500 = €400. You can save €200 at the start of the month and keep €200 as a margin.

The repayment takes 30% of your income, because 600 ÷ 2,000 = 0.30. These are example figures.

What changes when you take out a mortgage?

The repayment becomes a fixed cost for many years. Before you borrow, check how much of your income goes to loan repayments. In English it is your affordability ratio. See the guide What is the effort rate, and what should mine be?

Where FINOVA helps

We work out the purchase with you before going to the banks. In the home purchase simulator you can see your affordability ratio. See also What should be the ideal amount for my Emergency Fund?

Sources

• Banco de Portugal — How to draw up a household budget
• Banco de Portugal — Why it's important to draw up a household budget
• Todos Contam — Drawing up the budget (in Portuguese)
• Todos Contam — Planning the household budget (in Portuguese)

Sources checked on 22 September 2026.