UK finance jargon - in plain English
Everything you own minus everything you owe.
Net worth is the total value of your assets (things you own) minus your liabilities (things you owe). Assets include savings, investments, property value, pension pots, and any other valuables. Liabilities include mortgages, loans, credit card balances, and any other debts. The resulting figure can be positive or negative. Most people early in their careers or with large mortgages have a low or even negative net worth, which is completely normal. The direction of travel over time matters more than the number itself.
You have £8,000 in savings, a car worth £6,000, and a property worth £220,000. Your liabilities are a £185,000 mortgage and £2,000 in credit card debt. Your net worth is £47,000. If you track this every year and it is growing, you are moving in the right direction.
Asset values like property and investments fluctuate. Net worth is a snapshot, not a fixed figure. Pension values are often excluded from day-to-day calculations but are a significant asset worth including for the full picture.
People confuse a high income with a high net worth. You can earn a lot and have a low net worth if spending keeps pace with earnings. Building net worth is about what you keep, not just what you earn.