Glossary

15 essential terms for understanding your budgeting and personal finances.

• Smoothed budget

  A budgeting method that converts irregular annual charges (insurance, taxes, gifts, car maintenance) into predictable monthly contributions. Rather than absorbing spending spikes, you set aside a proportional share each month so that your current account is never caught off guard.

• Bucket account (themed account)

  A savings sub-account allocated to a specific goal — holidays, taxes, next car, renovation. Each bucket visually isolates an envelope of money to prevent it from being spent elsewhere. In Belgium, this typically means a second savings account or a logical sub-category.

• Saving capacity

  The maximum amount a household can set aside each month without cutting into its baseline standard of living. Calculated by subtracting all fixed and recurring variable expenses from net income. A key financial health indicator, distinct from the balance that happens to be left at month's end.

• Saving rate

  The share of net income actually set aside, expressed as a percentage. Formula: (monthly savings ÷ net income) × 100. The Belgian average hovers around 13-15 % according to the National Bank; a healthy rate toward financial independence typically sits between 20 and 30 %.

• Emergency fund

  A liquid reserve meant to cover the unexpected — job loss, major breakdown, medical bills, urgent repairs. Typically sized at 3 to 6 months of fixed costs for a salaried employee and 6 to 12 months for a freelancer. Must remain immediately available, so never locked away or invested in equities.

• Personal working capital

  A routine cash buffer that absorbs timing gaps between income and expenses within a single month — rent due on the 1st while salary arrives on the 25th, quarterly taxes, bulk grocery runs. Distinct from the emergency fund (which covers unforeseen events): working capital handles day-to-day life.

• Fixed costs

  Recurring expenses with a predictable amount and known due date — rent or loan repayment, insurance, telecom subscriptions, flat-rate utilities, council tax. By definition they vary little from month to month and are not renegotiable in the short term without a contract change.

• Variable costs

  Recurring expenses with fluctuating amounts — groceries, fuel, restaurants, leisure, clothing, gifts. Unlike fixed costs, they depend on consumption behaviour and can be adjusted in the short term. They are the main lever for quick savings when you want to grow your saving capacity.

• Regulated savings account

  A Belgian bank savings product whose minimum rate and tax regime are set by the State. Combines a base rate and a loyalty bonus (earned after 12 months). Interest is tax-exempt up to an annually indexed ceiling (1 020 € per person for 2026, 2 040 € for a married or legally cohabiting couple); above that, a 15 % withholding tax applies.

• Standing order

  A mandate given to your bank to automatically execute a recurring transfer — same amount, same beneficiary, same frequency. Used for rent, loan repayments, automated savings transfers. Distinct from a direct debit, which is initiated by the creditor and may vary in amount.

• Direct debit

  A standing authorisation given to a creditor (utility provider, telecom operator, landlord) to directly pull due amounts from the debtor's account. Unlike a standing order, the creditor initiates each payment and the amount can vary at every due date depending on the invoice.

• PSD2 (Payment Services Directive 2)

  A European directive in force since 2018 that governs payment services across the European Economic Area. It requires banks to open their account data and payment capabilities, via secure APIs, to authorised third parties — aggregators, payment initiators, financial management apps.

• Disposable income

  The amount available each month once all fixed costs and automated savings transfers have been subtracted from net income. It covers variable costs and leisure. A practical figure you can check day-to-day to know how much you can spend without knocking the monthly budget off balance.

• Compound interest

  The mechanism by which interest earned on a principal is added to that principal and itself generates interest in subsequent periods. The effect is exponential over long horizons: doubling the investment horizon nearly quadruples the total gain. Popularised by the (incorrectly) Einstein-attributed quote: "the eighth wonder of the world".

• 50/30/20 method

  A budgeting framework popularised by Elizabeth Warren, splitting net monthly income into three blocks: 50 % for unavoidable needs (housing, food, transport), 30 % for wants and leisure, 20 % for savings and debt repayment. A simple rule of thumb, not a rigid formula.