Breakdown is a Pro feature. Use it when one payment is made of several things and you want to remember what: a grocery run, a hardware-store receipt, a restaurant bill. In the transaction form, switch on Split into items.
Your current amount becomes the first item. Give each item a name and an amount, and use Add item for more — you need at least two, and there is no upper limit. To subtract something, such as a discount, press the minus button on that item and enter the amount without a sign. An item can't be zero, and the total of all items must stay above zero; until it does, Save is disabled and a message says why.
The transaction amount is always the sum of its items. A commission isn't an item — it stays on the transaction and is added on top, as usual. The account, category, date and exchange rate are still chosen once for the whole transaction.
On a transfer, the items belong to the sending account and are shown in its currency. The received amount is suggested from the total and the exchange rate, and you can still override it. In your list, a small badge on the row shows how many items a transaction has.
To go back to a single amount, switch Split into items off or delete items until one is left; Rasa Money asks you to confirm, because the item names are discarded. Breakdown isn't available on recurring transactions, debt payments or settlements, and imports create single transactions. Cloning a breakdown copies its items; a refund carries the total only.
If you move to Basic, existing breakdowns stay: the items and amount become read-only, while the date, category, account and note stay editable and you can still delete the transaction. Upgrade again and everything is editable.