1. One phrase, two very different meanings
A number of means “several” or “many”: the speaker is talking about an unspecified but noticeable quantity of individual things or people, not about counting them. Its role is equivalent to several or many.
The number of names the quantity itself as a specific figure: how many there are altogether. The focus is a statistic or total, rather than the things or people themselves.
A number of + plural count noun → “several/many X”; The number of + the same noun → “the quantity of X itself”.
- noun —
- A word naming a person, thing or idea: student, book, happiness.
A number of applicants withdrew before the final interview round.
A number of applicants withdrew before the final interview round.
The focus is the applicants themselves, not their count.
The number of candidates has grown steadily this hiring season.
The number of candidates has grown steadily this hiring season.
The focus here is the figure itself: the statistic, not the people.
A number of witnesses gave conflicting accounts of the accident.
A number of witnesses gave conflicting accounts of the accident.
There are several witnesses; the exact number does not matter here.
2. What actually controls agreement?
In the number of X, number is the head of the subject phrase. The noun after of only specifies what is being counted, so the verb agrees with number, not X: it is singular in this pattern.
When it means “several”, a number of functions as a quantifying expression with plural agreement: a number of invoices were paid. This is notional agreement — agreement by meaning — not a “notational” plural.
The number of overdue invoices was surprisingly low last quarter.
The number of overdue invoices was surprisingly low last quarter.
Was agrees with singular number, not invoices.
A number of invoices were paid late without any explanation.
A number of invoices were paid late without any explanation.
Were agrees notionally with several individual invoices rather than with the word number itself.
3. Form in negatives and questions
Negatives and questions follow the usual Present/Past Simple or Perfect rules: choose the auxiliary as in the affirmative, and it is the auxiliary that participates in negation or inversion.
Do not add an extra auxiliary or change the phrase itself when making a negative or question: the auxiliary reflects the singular or plural agreement.
A number of customers haven't received their refund yet.
A number of customers haven't received their refund yet.
Haven’t is plural, agreeing with a number of customers.
Has the number of customer complaints dropped this quarter?
Has the number of customer complaints dropped this quarter?
Question-form has comes before the number of; the subject remains singular.
Do a number of suppliers still use the old ordering system?
Do a number of suppliers still use the old ordering system?
Do is the plural form needed for a number of suppliers in the question.
Modifiers and the meaning of number
Adjectives such as great, large, small, considerable, growing and tiny can go between the article and number: they describe the quantity but do not cancel the agreement rule.
In the ordinary meaning “many / several people or things”, an adjective does not remove plural agreement: a large number of readers have… . But when a sentence discusses the numerical value itself, analyse number as a noun: a higher number is preferable. Meaning is decisive, not a alone.
A surprisingly large number of readers have cancelled their subscriptions.
A surprisingly large number of readers have cancelled their subscriptions.
Large before number does not change the main rule: plural have is still needed in this quantifying phrase with a.
The exact number of readers who cancelled remains unclear.
The exact number of readers who cancelled remains unclear.
Exact after the does not change the need for singular agreement: remains, not remain.
The typical pair and the limits of the simple rule
For the two meanings practised here, the contrast is stable: a number of members disagree means several members; the number of members is seven concerns the quantity itself.
Do not extend this to every sentence containing number. A certain number of participants is required can express a requirement for a particular quantity as a whole. Before choosing agreement, establish whether the sentence concerns people doing something or the numerical value itself.
A number of the board members strongly disagree with each other, yet the phrase still takes a plural verb.
A number of the board members strongly disagree with each other, yet the phrase still takes a plural verb.
Even when the participants differ greatly, a number of retains plural agreement.
The number of board members is fixed at seven, however differently they vote.
The number of board members is fixed at seven, however differently they vote.
Is remains singular regardless of how differently the people within the group vote.
6. Limits: when this is no longer the same pair
In the meanings “several items / the quantity of items”, number of is followed by plural countable units. For an uncountable quantity, use amount of information or a counting unit, as in a number of pieces of information. The noun number also has other constructions without of: a phone number.
Neighbouring quantifying expressions follow their own patterns. Each of normally takes a singular verb; either/neither of allows variation depending on usage. Majority/minority/proportion also cannot be reduced to one mechanical rule. The main point here is distinguishing several participants from the quantity itself.
A number of delays pushed the launch back by a week.
A number of delays pushed the launch back by a week.
Delays is a plural count noun; both a number of delays and the number of delays are possible phrases, depending on the intended meaning.
The amount of information in the report was overwhelming.
The amount of information in the report was overwhelming.
Information is uncountable, so use amount, not number; this is a different construction, outside this rule.
7. Using the distinction yourself: reports and facts
In business and academic language, this pair appears in descriptions of statistics, progress reports and explanations of causes. Choose the phrase according to what you actually want to say: refer to several individual cases or name the total figure.
When planning a sentence, decide the meaning first (several cases or the figure itself), then choose the article and verb: form follows meaning, not the other way around.
A number of team members raised concerns about the new deadline during the meeting.
A number of team members raised concerns about the new deadline during the meeting.
The aim is to refer to several people, not the total number of concerns.
The number of concerns raised at the meeting was noted in the minutes.
The number of concerns raised at the meeting was noted in the minutes.
The total figure matters here, not the participants themselves.
Common mistakes
Incorrect:The number of complaints have increased this month.
Correct:The number of complaints has increased this month.
In the number of, number itself is the singular head of the subject; have incorrectly agrees with complaints.
Incorrect:A number of volunteers has joined the clean-up project.
Correct:A number of volunteers have joined the clean-up project.
A number of acts as a plural quantifier meaning “several”, so have is needed, not has.
Incorrect:A large number of typos were find in the final draft.
Correct:A large number of typos were found in the final draft.
In the passive, were must be followed by the past participle found, not base find. Here, a large number of refers to many individual items.
Incorrect:The exact number of guests are still unknown.
Correct:The exact number of guests is still unknown.
Exact before number does not make the agreement plural: is remains because the subject is headed by number.
Incorrect:There are a number of unresolved issue on the agenda.
Correct:There are a number of unresolved issues on the agenda.
A number of refers to several countable issues, so plural issues is needed, not singular issue.
Incorrect:Have the number of applicants increased since last year?
Correct:Has the number of applicants increased since last year?
In a question with the number of, the auxiliary remains singular: has, not have.
Incorrect:Does a number of stores still accept cash-only payments?
Correct:Do a number of stores still accept cash-only payments?
A question with a number of needs plural do because the quantifier refers to several individual stores.
Incorrect:A number of feedback was collected after the workshop.
Correct:A number of comments were collected after the workshop.
Feedback is uncountable; number needs a plural count noun (comments), otherwise the phrase does not work grammatically.