English Formal vs Informal: The Complete Register Guide
Choosing the right register — formal or informal — is one of the most important skills in English. The same idea can sound professional or careless depending on the words you choose. This guide covers 48 contrasted examples across six key areas, from everyday vocabulary to academic writing and spoken English.
48 items · 6 topics
"commence / start"
"Commence" is formal; "start" is neutral/informal
"Formal: The meeting will commence at 9 a.m. Informal: Let's start the meeting."
"request / ask"
"Request" is formal; "ask" is everyday informal
"Formal: We kindly request your presence. Informal: Can you ask him to come?"
"assist / help"
"Assist" is formal; "help" is informal and conversational
"Formal: I would be happy to assist you. Informal: Can I help you with that?"
"obtain / get"
"Obtain" is formal; "get" is informal
"Formal: You may obtain a copy from reception. Informal: You can get a copy there."
"terminate / end"
"Terminate" is formal; "end" or "finish" are informal
"Formal: The contract will be terminated. Informal: The deal is ending."
"endeavour / try"
"Endeavour" is highly formal; "try" is everyday
"Formal: We will endeavour to resolve the issue. Informal: We'll try to fix it."
"sufficient / enough"
"Sufficient" is formal; "enough" is informal
"Formal: The evidence is sufficient. Informal: There's enough proof."
"consequently / so"
"Consequently" is formal; "so" is informal
"Formal: Consequently, the project was delayed. Informal: So we were late."
"passive vs active voice"
Formal writing uses passive; informal uses active
"Formal: The report was submitted by the team. Informal: The team submitted the report."
"long complex sentences"
Formal register uses complex multi-clause sentences
"Formal: Notwithstanding the challenges encountered, the committee reached a unanimous decision."
"contractions avoided"
Formal writing avoids contractions
"Formal: It is not possible. Informal: It's not possible."
"sentence fragments"
Informal speech and writing often use fragments
"Informal: Sounds good. See you then. Formal: That proposal sounds good. I look forward to seeing you."
"impersonal constructions"
Formal text often avoids "I" with impersonal phrases
"Formal: It is recommended that… Informal: I recommend that you…"
"subordinate clauses"
Formal writing stacks subordinate clauses
"Formal: Given that the deadline has been extended, it may be advisable to revise the scope."
"modal verbs for softening"
Formal uses "would", "may", "might"; informal uses "will", "can"
"Formal: Could you please review this? Informal: Can you check this?"
"ellipsis in speech"
Informal speech drops words; formal uses complete sentences
"Informal: Coming tomorrow? Formal: Will you be attending tomorrow?"
"Dear Mr/Ms [Surname]"
Standard formal salutation in letters and emails
"Dear Ms Johnson, I am writing to enquire about the position advertised."
"Hi / Hey [First name]"
Informal greeting used with colleagues or friends
"Hi Sarah, just wanted to check in about the report."
"To Whom It May Concern"
Formal opening when the recipient is unknown
"To Whom It May Concern: I am writing on behalf of our organisation."
"Yours sincerely / Yours faithfully"
Formal closings for letters; "sincerely" when name is known
"Yours sincerely, David Hughes. (Used when the name is in the opening.)"
"Best regards / Kind regards"
Semi-formal email closing, widely used professionally
"Kind regards, Anna. This works in most professional email contexts."
"Cheers / Take care"
Informal sign-offs used with people you know well
"Cheers, Tom. (Used in internal emails or messages with close colleagues.)"
"Good morning/afternoon"
Formal greeting at the start of a meeting or call
"Good morning, everyone. Thank you for joining today's session."
"What's up? / How's it going?"
Very informal greetings used with friends or close peers
"What's up? Haven't seen you in ages!"
"I am writing to inform you"
Formal phrase to state the purpose of an email
"I am writing to inform you that your application has been received."
"Just a quick note"
Informal opener for a brief message
"Just a quick note to let you know I'll be out of office on Friday."
"Please find attached"
Formal phrase to indicate an attachment
"Please find attached the revised proposal for your consideration."
"I've attached / Here's the file"
Informal way to mention an attachment
"I've attached the file — let me know what you think!"
"I would appreciate it if you could"
Formal polite request in email
"I would appreciate it if you could review the document by Thursday."
"Could you…? / Can you…?"
Semi-formal and informal ways to make a request
"Could you send me the report? / Can you send it over?"
"I look forward to hearing from you"
Formal closing statement in professional emails
"I look forward to hearing from you at your earliest convenience."
"Let me know / Get back to me"
Informal requests for a response
"Let me know if you have any questions. Get back to me when you can."
"This paper argues that"
Standard formal phrase to state a thesis
"This paper argues that climate change disproportionately affects low-income communities."
"I think / I believe"
Informal opinion markers, generally avoided in academic writing
"Informal: I think this is important. Academic: The evidence suggests this is significant."
"Furthermore / Moreover / In addition"
Formal discourse markers to add information
"Furthermore, the data indicates a significant correlation between the two variables."
"The findings suggest"
Hedged academic language for reporting results
"The findings suggest a strong positive correlation between stress and absenteeism."
"It can be argued that"
Formal academic phrase for presenting a position
"It can be argued that early intervention produces better long-term outcomes."
"lots of / a lot of"
Informal quantifiers avoided in formal academic writing
"Informal: A lot of studies show this. Academic: Numerous studies demonstrate this."
"Notwithstanding"
Formal concessive connective used in academic and legal writing
"Notwithstanding these limitations, the results remain statistically significant."
"As evidenced by"
Formal phrase to introduce supporting evidence
"As evidenced by the data in Table 2, output increased by 34% in the second quarter."
"gonna / going to"
"Gonna" is informal spoken; "going to" is neutral to formal
"Informal: I'm gonna call him later. Formal: I am going to contact him this afternoon."
"wanna / want to"
"Wanna" is very informal; avoided in any formal context
"Informal: Do you wanna join? Formal: Would you like to attend?"
"kind of / sort of"
Hedging expressions common in informal speech
"Informal: It's kind of complicated. Formal: It is somewhat complex."
"yeah / yes"
"Yeah" is very informal; "yes" is neutral to formal
"Informal: Yeah, that works for me. Formal: Yes, that would be acceptable."
"you know / I mean"
Filler phrases typical of informal spoken English
"Informal: It was, you know, quite difficult. (Not used in formal speech.)"
"basically / literally"
Overused informal adverbs common in casual speech
"Informal: I basically did all the work. Formal: I completed the majority of the work."
"hang on / one moment please"
"Hang on" is informal; "one moment" is formal
"Informal: Hang on, let me check. Formal: One moment, please. I will verify that."
"to be honest / frankly speaking"
"To be honest" is informal; "frankly" is more formal
"Informal: To be honest, I disagree. Formal: Frankly, I hold a different view."
Frequently Asked Questions
What is the difference between formal and informal English?
Formal English uses precise vocabulary, complete sentences, passive constructions, and avoids contractions and slang. It is used in business writing, academic papers, official letters, and professional settings. Informal English is more relaxed, uses contractions, colloquial words, and shorter sentences. It appears in conversations with friends, casual emails, and social media.
When should I use formal English?
Use formal English when writing to someone you do not know well, in academic writing, job applications, official correspondence, legal documents, and professional presentations. When in doubt, formal is safer — you can always relax your register once a relationship is established.
Can I mix formal and informal English?
Yes, but with care. Semi-formal English — used in many workplace emails — blends polite structure with natural phrasing. The key is consistency: avoid jumping between very formal and very casual within the same document or message.
How does register affect vocabulary choice?
Formal English tends to use Latinate words (commence, sufficient, endeavour) while informal English prefers shorter Germanic equivalents (start, enough, try). Formal vocabulary also tends to be longer, more specific, and avoids phrasal verbs like "get" or "put up with".
Does spoken English have formal and informal registers too?
Absolutely. Spoken formal English is used in presentations, job interviews, academic talks, and meetings with senior figures. It avoids fillers (you know, like), contractions, and slang. Informal spoken English is used in everyday conversation and includes features like gonna, wanna, yeah, and discourse fillers.
The best way to internalise register is to hear it used naturally. Explore authentic English video content and notice how speakers shift between formal and informal styles.
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