"Top up" is a phrasal verb commonly used in informal contexts, though it can also appear in more formal settings, particularly in written correspondence related to transactions or services. It generally means to add to the existing amount of something to reach a desired level or replenish a balance. In British English, it is frequently used when referring to adding funds to a pre-paid card or mobile phone account (“I need to top up my phone credit”). In broader contexts, it can also refer to refilling a container or glass (e.g., "Shall I top up your drink?"). Its application is quite versatile, including financial contexts like topping up an investment, as well as more everyday interactions. The verb "top up" implies a relatively small, supplementary addition rather than a complete refill or replacement, which helps distinguish its use from similar terms like "refill."
B1
Intermediate
1. To add more of a substance to bring something up to the desired level.
She went to the kitchen to top up her tea.
Before the guests arrived, he topped up the punch bowl.
2. To replenish or add more money to an account or card.
I need to top up my mobile phone with more credit.
She topped up her travel card for the subway.
3. To increase a resource to a satisfactory or maximum level.
After dinner, the waiter came by to top up our wine glasses.
They decided to top up their energy levels with a quick nap.
