"Data Is" or "Data Are"? Singular vs Plural

Both "data is" and "data are" are correct. Data are treats the word as a plural, which is its original Latin form and still the norm in much scientific and academic writing. Data is treats it as a mass noun, like information, and is now standard in everyday, business and technology English.

So the real question is not grammar but audience. A journal article and a product dashboard can reasonably make opposite choices, as long as each stays consistent.

Quick answer: In scientific and academic writing, use data are unless your style guide says otherwise. In business, tech, journalism and everyday writing, data is is standard and natural. Match your words: this data is or these data are, never these data is.

On this page

1. Where the word comes from
2. Count nouns, mass nouns and why data can be both
3. What style guides tend to say
4. Tricky constructions
5. US vs UK vs Australia
6. Example sentences
7. Common mistakes
8. Other Latin and Greek plurals
9. Editing exercise: fix the mixed paragraph
10. A memory trick
11. Practice quiz
12. Settling it in your own writing

Where the word comes from

Data is the plural of Latin datum, "something given," from the verb dare, "to give." In English, datum was used for a fact or premise given as the basis of an argument or calculation, and data for a set of them.

For a long time, educated usage followed the Latin and treated data as plural: These data suggest.... As computing and statistics spread in the twentieth century, data increasingly came to mean an undifferentiated mass of information, something you store, transfer and analyze in bulk. In that sense, people began to treat it grammatically like information, sand or traffic: a mass noun that takes a singular verb.

Dictionaries in the US, UK and Australia now record both uses. Usage guides that once objected to singular data have largely softened, although many still prefer the plural in formal scientific writing.

Pronunciation

There are three common pronunciations, all acceptable:

• DAY-tuh: very common in the UK, Australia and the US
• DAT-uh (first syllable as in cat): common in the US and Australia
• DAH-tuh: heard in some regions and among some speakers

Datum is usually DAY-tum.

Count nouns, mass nouns and why data can be both

English nouns fall roughly into two grammatical groups.

Count nouns refer to things you can count individually: one file, two files. They have singular and plural forms and take many and fewer.

Mass (non-count) nouns refer to stuff treated as an undivided whole: information, water, furniture, research. They take singular verbs and much and less.

Plural data is a count noun in which each datum is a separate item. Singular data is a mass noun. That is why the verb changes:

There is no grammatical contradiction here. English has other nouns that shift between count and mass use, such as chicken (two chickens / some chicken) and cake. Thinking of data as a mass noun is not a mistake; it is a change in how speakers conceive the thing.

For a related grammar point, see less vs fewer, which also hinges on the count-versus-mass distinction.

When the plural reading feels natural

Even people who normally say data is sometimes switch when they are thinking of separate measurements:

• The data were collected at five sites between 2019 and 2022.
• These data come from three independent surveys.

And people who normally say data are may find the singular more natural for a big digital mass:

• How much data is left on your phone plan?
• Data is the new oil, according to the keynote speaker.

"Data are left on your phone plan" or "Many data are left" would sound strange to almost anyone. That shows the mass-noun use is now a settled part of the language.

What style guides tend to say

Different communities have different norms. Speaking in general terms:

• Scientific journals and academic style guides, including APA style, have traditionally treated data as plural. Many researchers follow that habit regardless of guide.
• Some scientific publishers now accept or even prefer the singular, especially in data science and computing.
• News organizations in the US, UK and Australia often allow data as a singular mass noun in general reporting, sometimes keeping the plural for scientific contexts.
• Technology companies and business writing overwhelmingly use the singular.

When in doubt, the house style wins. If there is none, think about your audience: researchers may notice singular data, while business readers may find plural data fussy.

Tricky constructions

Most agreement problems with data show up not in short sentences but in longer ones, where other words get between the subject and the verb.

"Data set," "dataset" and "data point"

When data is used as a modifier before another noun, the head noun controls the verb: The data set is large. The data points are scattered. Data itself is not the subject here, so the singular-or-plural debate does not arise. Data set and dataset are both common spellings; technical fields increasingly prefer the closed dataset, while some editors keep it as two words.

Quantity phrases

With phrases such as a lot of, most of, some of and all of, the verb usually follows your treatment of data:

• Most of the data is missing. (mass noun)
• Most of the data are missing. (plural)

With the majority of, many writers find the plural more natural when they are thinking of individual entries: The majority of the data were collected online. If that sounds fussy for your audience, rephrase: Most responses were collected online.

"Big data" and compound terms

Terms such as big data, open data, metadata and personal data are almost always treated as singular mass nouns, even in fairly formal writing: Big data is reshaping retail. Personal data is protected under privacy law. Writing Big data are reshaping retail is not wrong, but it will strike most readers as unusual.

Pronouns later in the sentence

If you choose plural data, refer back with they and them; if singular, use it. Mixed pronouns are the most common slip in long reports: The data was collected in May, and they show... should be and it shows or should start The data were.

Headlines and charts

Short labels such as chart titles and table headings often avoid verbs altogether (Sales data, 2024), which neatly sidesteps the issue. When a caption does need a verb, keep it consistent with the body text.

US vs UK vs Australia

There is no systematic national difference in how data is treated. In all three countries:

• Everyday, business and technology writing mostly uses singular data is.
• Scientific and academic writing often uses plural data are.
• Both uses appear in quality newspapers.

Pronunciation varies more than grammar. DAY-tuh is the dominant pronunciation in Britain; Americans and Australians use both DAY-tuh and DAT-uh widely. British and Australian English also more readily use plural verbs with collective nouns in general (the team are), but that habit does not specifically change how data behaves.

Example sentences

Everyday and consumer

1. My phone plan includes 40 gigabytes of data, but most of it is gone already.
2. Is your data backed up anywhere?
3. The app says it doesn't sell your data to advertisers.
4. Mobile data is patchy once you leave the coast road near Byron Bay.
5. That data is out of date; check the council website.

Workplace and email

6. The sales data for the Leeds branch is attached.
7. Once the data is cleaned, we can build the dashboard.
8. Our customer data is stored on servers in Sydney.
9. The data shows a clear rise in returns after the price change.
10. Please don't share this data outside the team.
11. How much data do we need before the pilot results are reliable?

Academic and scientific

12. The data were analyzed using a mixed-effects model.
13. These data suggest a seasonal pattern in admissions.
14. Data were collected from 1,200 households across Ohio and Kentucky.
15. The data are consistent with earlier findings from the Queensland cohort.
16. Each datum was checked against the original field notes.
17. Missing data were handled by multiple imputation.

News style

18. New data from the Office for National Statistics shows inflation easing.
19. The data, released on Tuesday, suggests house prices in Perth are still rising.
20. Health officials said the data were preliminary and could change.

Technical "datum"

21. All elevations are measured from the national datum.
22. On engineering drawings, the datum is the reference surface from which dimensions are taken.

Common mistakes

❌ These data is incomplete. ✅ These data are incomplete. / This data is incomplete. Make the determiner and verb agree.

❌ The data shows a trend, and they are reliable. ✅ The data shows a trend, and it is reliable. / The data show a trend, and they are reliable. Keep pronouns consistent with your choice.

❌ We need less datas. ✅ We need less data. Data does not take an -s.

❌ A data shows the problem. ✅ A data point shows the problem. / One figure shows the problem.

❌ (journal article) The data is presented in Table 2. ✅ (journal article) The data are presented in Table 2. Not ungrammatical, but many journals expect the plural.

❌ Many data was lost in the crash. ✅ A lot of data was lost in the crash. / Much of the data was lost.

Other Latin and Greek plurals

Data is part of a group of borrowed plurals that English is gradually naturalizing at different speeds.

Agenda has gone all the way: nobody says "the agenda are." Criteria and phenomena have not: "a criteria" is still widely regarded as an error. Data sits in between, which is exactly why it causes debate. If you like this kind of question, our guide to among vs amongst vs between looks at another case where older rules and modern usage disagree.

Editing exercise: fix the mixed paragraph

Agreement slips with data rarely happen in one sentence. They creep in across a paragraph, especially when several people have edited a report. Here is a short passage from a draft project update. It switches between singular and plural four times. Rewrite it in the singular, as you would for a business audience.

The survey data were collected in March from 600 customers in Manchester and Melbourne. This data shows a clear preference for online booking, and they also suggest that younger customers want text reminders. Most of the data is complete, but some of these data are missing postcodes.

One corrected version (singular throughout):

The survey data was collected in March from 600 customers in Manchester and Melbourne. This data shows a clear preference for online booking, and it also suggests that younger customers want text reminders. Most of the data is complete, but some of it is missing postcodes.

What changed: were became was; they also suggest became it also suggests; and some of these data are became some of it is. If you were preparing the same passage for a journal, you would make the opposite edits: data were, these data show, they also suggest, most of the data are and some of the data are.

The fastest way to check your own work is to search the document for data and read only the verb and pronoun that follow each hit.

A memory trick

"Data are for the lab; data is for the laptop." If you are writing a methods section, think plural: many separate measurements. If you are talking about storage, downloads, analytics or "big data," think mass noun, like information. Whichever you pick, check that this/these and is/are point the same way.

Practice quiz

Choose the best option for the context.

1. (Medical journal) The data ___ collected over 18 months. (was / were)
2. (Phone plan ad) Unlimited data ___ included. (is / are)
3. ___ data are inconsistent with the original hypothesis. (This / These)
4. (Business email) The quarterly data ___ attached. (is / are — most natural)
5. We have ___ data than we expected. (less / fewer)
6. One ___ was clearly an outlier. (data / datum or data point)

Answers

1. were – scientific writing usually treats data as plural.
2. is – consumer and tech usage treats data as a mass noun.
3. These – plural determiner matches plural "are."
4. is – the singular is standard in business writing.
5. less – mass-noun data takes less.
6. datum or data point – a single item is not "a data."

Settling it in your own writing

Choose once per document. If you are writing for scientists, reviewers or a style guide that treats data as plural, write data are and these data. Everywhere else, data is is standard and sounds natural, so use it with confidence. What readers notice is not which choice you make but whether you switch halfway through. For another place where formal and informal rules split, see who vs whom.