10 differences between formal and informal language

The way you talk to your friends and family is probably different than how you communicate with your colleagues or manager at work. Just like in your mother tongue, when it comes to the English language there’s different formalities that are appropriate in formal and informal settings.  

Knowing when to use formal or informal English will depend on the people you are around and the general environment. If you work in a cross-cultural setting, or are in a group of people you don’t know very well, it’s often a better idea to stick to formal language where possible. This helps reduce the risk of any misunderstandings and means you will sound polite and professional.  

When should I use formal and when should I use informal language?

Generally, formal language is used in situations that are more serious, official or work-related. You might want to use formal language and mannerisms when meeting someone for the first time, but over time you will learn to adapt the formality of your communication dependent on the situation you find yourself in.

As a general rule, informal language is used in situations that are more relaxed and involve people we know well. Additionally, the language we use when we write is more formal than the language and style of communication we use when we speak.

Here are 10 tips on how to use formal and informal language: 

  1. Vocabulary

In English, there are lots of words that mean the same thing, but certain choices will be more suitable in formal or informal settings. If you are writing a formal email, you might begin the email with ‘Dear XXX’ whereas an informal greeting could be ‘Hey XXX’.

Some other examples of formal VS informal vocabulary include:






Get well





  1. Tone, speed and volume

Tone is a great way to indicate how you feel about a subject. By varying your tone or volume you can change the meaning of what you are saying. It is common across several languages that raising your voice will make what you are saying sound more aggressive or more urgent. In formal settings, a neutral or polite tone and an average pace and volume is the best bet, but you can usually mirror the tone, speed and volume of the person or people you are talking to if you are unsure.

  1. Grammar

When using formal language, grammar can be more complex and sentences are generally longer. Consider the different ways you could ask for directions:

Formal: Excuse me, please could you tell me where the shop is?

Informal: Where’s the shop?

If you are writing a formal letter, you will need to spend more time thinking about your grammar than if you are writing a text to a friend or speaking in conversation. Learn more about grammar rules here.

  1. Pronunciation

Proper pronunciation is considered an indicator of politeness and formality. If you are mumbling – e.g. speaking quietly without opening your mouth fully – your speaker may not be able to understand you properly and it can be seen as rude or lazy.

  1. Avoid verb contractions

Verb contractions are used to combine/shorten two words e.g. instead of saying ‘We will be late’ you can say ‘We’ll be late.’ This is quite an informal way to write, so in situations where you are expected to produce extremely formal written work, it can be a better idea to stick to the full word rather than contractions.

  1. Use of abbreviations or idioms

Abbreviations are commonly known ways to shorten long words, phrases, and proper nouns. Say for example, you are writing a report on NASA, a trend in formal writing, is to write out the initial word, phrase, or proper noun then write the abbreviation in parentheses e.g. National Aeronautics and Space Administration (NASA). After you have written the full name once, you can usually use the abbreviation for the remainder of the text. In informal writing, you could just use the abbreviations.

  1. Use of colloquial language, slang and idioms

Colloquialisms are informal terms or phrases used in casual conversation. Slang is usually associated with a certain place and will vary in different parts of the UK. Additionally, idioms are popular phrases that are well-known in the English language and used to illustrate an idea or sentiment in a short and snappy phrase. They are quite an informal way to communicate but are not inappropriate in working environments. Learn more about English idioms here.

  1. Gesturing (when speaking)

Similar to tone, speed and volume during conversations, some people become enthusiastic and use gestures or hand signals with their friends that may not be appropriate in a more formal setting. You can get to grips with formally appropriate gesturing or hand signals over time.

  1. Emoji use (when writing)

If you are texting your friend of course it is normal to use emojis or GIFs to express yourself, but this is not appropriate when it comes to academic writing or even work emails.

  1. Structure (when writing)

If you are writing something more formal, such as an essay, you will need to consider the structuring of your writing more than you would if you’re writing a message to a friend. In an English language course, you will learn about essay structuring during your classes so this will improve over time.

Ready to put this knowledge into practice?

If you want to improve your English language skills, getting to grips with the differences between formal and informal writing is an important step. If you are writing, the most important thing to consider, in terms of style, is your reader and the topic. If you are writing about something serious or writing in an essay-style, formal writing is best. If you are chatting with your family or friends then informal communication is more appropriate.

If you enrol on an English course, you will get to practise speaking and writing in different scenarios and will naturally familiarise yourself with formal and informal English. Knowing when to use informal language is a skill that develops as your confidence in the language grows.

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