wrong preposition: 'On addition' (In addition)

Using 'on addition' is non-idiomatic. Use 'in addition' (or 'in addition to + noun') to mean 'also' or 'besides', or use simpler alternatives like 'also' or 'plus' for a more natural tone.

Below: short rules, many wrong→right pairs, quick rewrites, and tone-specific examples for work, school, and casual writing.

Quick answer

Replace 'on addition' with 'in addition' (as a connector) or 'in addition to' (before a noun). For a less formal tone, use 'also', 'plus', or 'besides'.

'In addition' = furthermore: 'In addition, we reviewed the budget.'
'In addition to' + noun = alongside something: 'In addition to the budget, attach the forecast.'
Casual alternatives: 'also', 'plus', 'besides'.

Why 'in addition' - core explanation

'In addition' is the idiomatic way to add information. It appears either as a sentence connector or as a prepositional phrase with 'to' before a noun phrase.

'On' expresses position, contact, or time-not logical addition. That's why 'on addition' sounds wrong.

Connector: 'In addition, [clause].' - adds another point.
Prepositional: 'In addition to [noun], [clause].' - adds an item alongside another.

Connector example: In addition, we need two more volunteers.
Prepositional example: In addition to the volunteers, we must order supplies.

Grammar note: placement and punctuation

When 'In addition' starts a sentence as a connector, follow it with a comma. 'In addition to' must be followed by a noun phrase and does not take a comma before that noun phrase.

Correct: 'In addition, please review the file.'
Correct: 'In addition to the file, attach the spreadsheet.'
Incorrect: 'On addition, please review the file.' or 'In addition with the file...'

Punctuation: 'In addition, I recommend reallocating funds.'
No comma: 'In addition to her salary, she receives a bonus.'

Real usage and tone: work, school, casual

Match formality to the context. Use 'in addition' or 'in addition to' in formal and neutral writing; use 'also', 'plus', or 'besides' in speech and informal messages.

Work (formal): 'In addition to the quarterly report, attach the updated forecast.'
Work (email): 'In addition, please confirm your availability for the meeting.'
School (essay): 'In addition to the main study, the paper examines long-term trends.'
School (lab): 'In addition to the samples, include the blank control.'
Casual: 'Also, I'll bring drinks.' or 'Plus, we can stop for ice cream afterward.'

Common examples: wrong → right pairs

Replace 'on addition' with 'in addition' or choose a simpler alternative. Realistic pairs below show common sentence shapes.

Wrong: On addition to the team, we hired two developers.
Right: In addition to the team, we hired two developers.
Wrong: Please attach your references on addition to your CV.
Right: Please attach your references in addition to your CV.
Wrong: On addition, we must review the budget before Friday.
Right: In addition, we must review the budget before Friday.
Wrong: On addition to the gift, she included a handwritten note.
Right: In addition to the gift, she included a handwritten note.
Wrong: On addition to the points above, consider the timeline.
Right: In addition to the points above, consider the timeline.
Wrong: We will, on addition, provide training sessions next month.
Right: We will, in addition, provide training sessions next month.
Work wrong: On addition to the quarterly figures, send the projections.Work right: In addition to the quarterly figures, send the projections.
School wrong: On addition to the literature review, include a methodology section.School right: In addition to the literature review, include a methodology section.
Casual wrong: On addition, I'll bring chips to the party.Casual right: Also, I'll bring chips to the party. (Or: In addition, I'll bring chips.)

Try your own sentence

Judge the whole sentence, not just the phrase. Read it aloud: if 'in addition' sounds stiff, swap in 'also' or restructure the sentence.

Rewrite help: quick patterns and edits

Three quick editing steps: replace 'on' with 'in' when appropriate; pick 'in addition' (connector) or 'in addition to' (before a noun); or use 'also'/'additionally' or combine clauses for flow.

Pattern A (connector): 'In addition, [clause].' → 'In addition, we will review the plan.'
Pattern B (prepositional): 'In addition to [noun], [clause].' → 'In addition to the plan, review the timeline.'
Alternatives: 'Also' / 'Additionally' / 'Plus' or merge: 'We will review the plan and the timeline.'

Rewrite 1: Original: 'On addition to my schedule, I can help.' → 'In addition to my schedule, I can help.' Or: 'I can help as well.'
Rewrite 2: Original: 'Please include the data on addition to the appendix.' → 'Please include the data in addition to the appendix.' Or: 'Please also include the data in the appendix.'
Rewrite 3: Original: 'On addition, we delayed the launch.' → 'In addition, we delayed the launch.' Or: 'We also delayed the launch.'
Rewrite 4: Original: 'Send the slides on addition to the notes.' → 'Send the slides in addition to the notes.' Or: 'Send both the slides and the notes.'
Rewrite 5: Original: 'On addition to the committee, we invited external reviewers.' → 'In addition to the committee, we invited external reviewers.' Or: 'We also invited external reviewers.'
Rewrite 6: Original: 'On addition, confirm the venue.' → 'In addition, please confirm the venue.' Or: 'Please also confirm the venue.'

Memory trick: three quick cues

Use small cues to spot the error fast.

'Add → In' - if you mean to add information, choose 'in'.
'To + noun? Use "in addition to".'
If it sounds clumsy, substitute 'also' or 'additionally' and re-check.

Proofread tip: Search your draft for 'on addition' and change it to 'in addition' or a simpler alternative.

Similar mistakes to watch for

Confusing 'on' and 'in' here often coincides with other preposition or adverb issues.

'Additionally' and 'In addition' are often interchangeable at the start of a sentence: 'Additionally, we noted...' vs 'In addition, we noted...'.
'Besides' is more informal and can add a contrast: 'Besides, I don't agree.'
Don't confuse 'upon' (meaning 'after' or 'on top of') with 'in addition'.

Usage fixes: Wrong: 'In addition with the report...' →
Right: 'In addition to the report...' or 'Along with the report...'
Usage fixes: Wrong: 'Upon addition, we will...' →
Right: 'In addition, we will...' (if you mean 'also')

Spacing, punctuation and hyphenation notes

No hyphens inside 'in addition' or 'in addition to'. Use a comma after 'In addition' when it begins a sentence. Avoid extra spaces or incorrect hyphenation.

Correct: 'In addition, please review.'
Correct: 'In addition to the report, attach the data.'
Do not write: 'In-addition', 'in addition-to', or 'On addition'.
Note: 'Add-in' (hyphenated) refers to software plug-ins and is unrelated to 'in addition'.

FAQ

Is 'on addition' ever correct?

Not to mean 'besides' or 'furthermore.' Treat 'on addition' as a non-idiomatic error; use 'in addition' or 'in addition to'.

Can I use 'additionally' instead?

Yes. 'Additionally' works like 'In addition' at the start of a sentence-choose based on rhythm and clarity: 'Additionally, we improved the process.'

Do I need a comma after 'in addition'?

If 'In addition' begins the sentence as a connector, use a comma. Do not put a comma before a noun phrase after 'in addition to'.

What's the fastest fix in casual writing?

Swap 'on addition' for 'also', 'plus', or a short rephrase: 'I'll also...' or 'I'll bring...' These read naturally in conversation.

How can I stop typing 'on' by mistake?

Use the proofreading cue 'Add → In', search for 'on addition' in your draft, and add an editing note to watch common prepositions.

Want a quick check?

Try replacing 'on addition' with 'in addition' or a simpler alternative and read the sentence aloud. If you edit prepositions often, paste a sentence into a grammar tool to see suggestions.