Moving abroad? Switch your budget to a new currency without rewriting your history

Priya's budget was $3,255 a month in Austin. At a rate of 0.90 euros to the dollar, that converts to €2,929.50 for her new life in Lisbon. After her first full month there, she actually needed €2,270, because rent, transport, and groceries cost different amounts in a different city. Priya and the rate are fictional, but the lesson holds: converting a budget gives you a starting point, not a plan.

The harder question is what to convert at all. Convert everything, including last year's transactions, and your history no longer matches your bank statements. Convert nothing, and your plans sit in a currency you no longer spend. This guide sorts each part of your money into one of two groups, then walks through rounding and the first-month check.

Which parts of your budget should you convert?

Ask one question about each record: does it describe what already happened, or what you plan to do? History stays as it was. Plans move to the new currency.

The same split keeps your records useful later. When you look back at last year's spending, you see what you really paid. When you look at this month's budget, every number is in the currency in your wallet.

Which exchange rate should you use?

Use today's market rate for the first conversion. You will round and adjust the result anyway, so the difference between one reasonable rate and another barely matters for a budget. For a neutral reference, the European Central Bank publishes euro reference rates around 16:00 CET each working day, though it says they are for information only and not for transactions.

The rate matters more when you move real money. The rate your bank or transfer service gives you is usually a little worse than the market rate, because providers add a margin, and some charge a fee on top. The guide to recording cross-currency transfers and fees shows how to record the amount sent, the amount received, and the fee, so moving your savings abroad does not show up as spending.

How do you round and adjust the converted budget?

Convert each category, round it to a number you would actually budget, then replace it with real costs as they appear. Here is Priya's budget at each stage:

Rent comes from the lease, not the conversion. Transport fell because Priya sold the car and now buys a monthly transit pass. Dining out stayed the same because it was a choice, not a price. The rounded column is still useful: it gave her a workable budget for the weeks before she knew the real numbers.

If you are rebuilding from scratch rather than converting, the budget builder is a faster way to set new categories around your new income.

What about bills you still pay in your old currency?

Moving rarely ends every dollar bill at once. A student loan, a phone plan you are winding down, or a service that still bills in dollars can stay for months. You have two options:

• Keep a small budget in the old currency for just those bills. Each one is tracked at its real amount, and nothing swings with the exchange rate.
• Budget them at a converted estimate with a little headroom. This keeps everything in one budget, but the actual charge will move as the rate does.

If a card charges a foreign transaction fee on those payments, the fee is a real cost. Count it, or move the bill to an account that does not charge one.

When should you recheck the new budget?

After your first full month of spending in the new currency, then again after three months. The first check replaces converted guesses with real costs, as Priya did. The second catches what one month misses, such as a quarterly bill, a deposit, or the cost of furnishing a new home.

Recheck your savings goals at the same time. An emergency fund sized for American rent may be too large or too small for your new costs. The emergency fund calculator can recompute it from your new monthly expenses.

How do you switch currency in Nethaven?

Nethaven sorts your records this way when you change your main currency, on mobile or the web. The steps are in changing your main currency.

• Choose what converts. Active budgets in your old currency (with this period's category amounts), savings goals, recurring bills, and debts each have their own switch and convert at today's market rate, shown on the first screen.
• Past transactions never convert. They keep the amount and currency they were recorded in.
• Review the budget amounts. Round to clean numbers, or type your own amount for any category before you confirm.
• Check anything you leave off. An item you do not convert keeps its number and is shown in the new currency, so a $20,000 loan left off would read as €20,000. Leave an item off only when its number is already right in the new currency.
• Undo from the confirmation screen. Undo switch restores every converted amount and your previous currency. Once you close that screen, you switch back manually.

A budget you set to another currency on purpose is left alone by the switch, which is how you keep a small dollar budget for leftover bills. You can create a budget with its own currency at any time. The budgeting overview and savings goals guide cover the rest of the setup.