Cool MateBack when vs Formerly
When to use each in English, with meaning, register, and examples.
Back when
Top 2,000 (common)
Formerly
FormalBeyond 10,000 (less common)B2adverb
Most formal: FormerlyMost common: Back when
| Back when | Formerly | |
|---|---|---|
| Pronunciation | 🇬🇧 //bæk wɛn//🇺🇸 //bæk wɛn// | 🇬🇧 /["/ˈfɔːməli/"]/🇺🇸 /["/ˈfɔːrmərli/"]/ |
| Meaning | A phrase used to talk about a time in the past. | in the past; before now |
| Example | I remember back when we used to play outside until dark. | Namibia, formerly known as South West Africa |
| Register | Neutral | Formal |
| How common | Top 2,000 (common) | Beyond 10,000 (less common) |
| CEFR level | - | B2 |
| Part of speech | adverb | |
| Collocations | back when I was young, back when things were different, back when we had fun | formerly a leader, formerly known, formerly used |
| Antonyms | - | currently, now |
| Common mistakes | Using it with present tense instead of past., Omitting necessary context in sentences., Confusing it with 'back then' which may imply a longer time span. | Confused with 'formally' — 'formerly' relates to the past, while 'formally' relates to official contexts., Omitting it when describing past roles or states, which can lead to ambiguity. |
| Usage notes | Used in storytelling or reminiscing about past experiences. Avoid in formal writing; suitable in casual conversation. | Use 'formerly' to describe something that was true in the past but is no longer the case. It is more formal than saying 'used to'. Avoid in casual conversations. |
Frequently asked questions: Back when vs Formerly
What's the difference between Back when and Formerly?
Back when: A phrase used to talk about a time in the past. Formerly: in the past; before now
Which is more formal: Back when and Formerly?
Formerly is the most formal of these.
Which is more common: Back when and Formerly?
Back when is the most common in everyday English.
Can you show an example of each?
Back when: I remember back when we used to play outside until dark. Formerly: Namibia, formerly known as South West Africa
Can I use Back when and Formerly interchangeably?
Not always. Back when and Formerly are related and overlap in some contexts, but they differ in register, how common they are, and usage, so swapping one for another can change the meaning or tone. Check the differences above before substituting.