Population estimates by marital status and living arrangements quality and methods guide, England and Wales

We produce annual statistics on population estimates by marital status and living arrangements of the resident population aged 16 years and over in England and Wales. These include characteristics of age and sex. The estimates are calculated by applying legal marital status and living arrangement distributions from the household dataset of the Labour Force Survey (LFS) to the mid-year population estimates for England and Wales.

The LFS does not cover those living in communal establishments such as care homes, prisons or military barracks. Therefore, there is a degree of undercoverage within the survey distributions, which is applied to the mid-year population estimates for the total population.

As with any set of survey-based statistics, these were produced using a sample and would vary were another sample taken in its place.

These are accredited official statistics.

We restructured and made minor updates to this guide on 15 October 2025. We made no important changes to quality and methods.

For more information on past and upcoming changes, go to Changes and their effects on comparability over time.

We present statistics on population estimates by marital status and living arrangements for the resident population aged 16 years and over in England and Wales in three separate datasets:

• Population estimates by marital status and living arrangements for England and Wales
• Population estimates by marital status and living arrangements for England
• Population estimates by marital status and living arrangements for Wales

Breakdowns in the datasets

The datasets include breakdowns by the different forms of marital status and living arrangements.

Legal marital status and living arrangement categories

• never married or civil partnered
• married
• civil partnered
• divorced [note 1]
• widowed [note 2]
• living in a couple: married or civil partnered
• living in a couple: cohabiting - never married or civil partnered
• living in a couple: cohabiting - previously married or civil partnered
• not living in a couple: never married or civil partnered
• not living in a couple: previously married or civil partnered

Statistics for married people are further broken down into opposite sex and same sex. Tables are split by sex. Age groupings are provided where possible, but these are different for the individual countries and the combined countries dataset, with the England and Wales combined dataset having more detailed age groupings.

Notes for What the statistics cover

1. Divorced includes those who have legally dissolved their civil partnership.

2. Widowed includes those who are a surviving civil partner.

Where the data come from

Labour Force Survey

The Labour Force Survey (LFS) is a quarterly social survey of the resident population in private households in the UK. It covers people in private households, NHS accommodation, and students in halls of residence whose parents live in the UK. Such students are included through proxy interviews with their parents.

The main purpose of the survey is to provide information on the UK labour market, but it includes data on a variety of other variables, such as marital status and living arrangements. The survey does not cover the 2% of the population who live in communal establishments such as prisons and nursing homes.

Each quarter's LFS sample is composed of around 35,000 households containing around 75,000 individuals and is made up of five waves. Each wave is interviewed in five successive quarters, so that in any one quarter, one wave will be receiving their first interview, one wave their second and so on, with one wave receiving their fifth and final interview. So, there is an 80% overlap in the samples for each successive quarter, and the samples for the sixth quarter and the first quarter have no common elements.

The LFS household datasets are produced on a quarterly basis each year (January to March, April to June, July to September and October to December). Population estimates by marital status and living arrangements use the April to June quarter each year as this includes the mid-year point (30 June).

The LFS household dataset differs from the person-level dataset in the way that the weighting is applied to the sample. The household dataset ensures that the weight given to each member of the same household is the same. The person-level dataset, which is more commonly used for information on the labour market, includes only individual weights, which usually differ between members of the same household. The Labour Force Survey user guide: volume 8 recommends the use of the household dataset when analysing people by marital or cohabitation status.

Surveys, such as the LFS, provide estimates of population characteristics rather than exact measures. In principle, many random samples could be drawn from the population and each would give different results since each sample would be made up of different people who would give different answers to the questions asked on the LFS. The spread of these results is the sampling variability, which generally reduces with increasing sample size.

Confidence intervals can be used to present the sampling variability. A 95% confidence interval can be interpreted as the interval within which 95 times out of 100, the true value will lie if the sample were repeated 100 times. Pragmatically, if you assume the confidence interval contains the true mean, you will be wrong 5% of the time.

Sampling and non-sampling error, along with information on measuring error, can be found in our Labour Force Survey (LFS) quality and methodology information. More information can be found in our Labour Force Survey (LFS) performance and quality monitoring reports and Labour Force Survey (LFS) user guide.

Mid-year population estimates

The annual mid-year population estimates provide the number of people by single year of age and sex who are usually resident in England and Wales on 30 June of the reference year. We calculate and usually publish them annually in June. The data published each year refer to the previous mid-year. They are the official population estimates for England and Wales.

More information about the quality and methodology of the mid-year population estimates is available.

How we produce the statistics

Weighted estimates from the LFS by age group and sex are calculated for each year, and for each legal marital status or living arrangement. Although the LFS is a survey of the UK, only estimates for England and Wales are used in the production of population estimates by marital status and living arrangements.

The estimates from the LFS are then converted into percentages for each age group. Mid-year population estimates for each year are then grouped into the corresponding age groups. Finally, the percentage of people in each age group by marital status or living arrangement is multiplied by the number of people in the mid-year population in the corresponding age group to obtain the final estimates.

Estimates for England and Wales separately are not expected to sum to England and Wales as a whole because the methodology used applies weighted proportions for each geography to the appropriate mid-year estimates. When we apply proportions to the population of England and Wales as a whole, we use weights that reflect the combined population structure. However, when we apply the same proportions separately to England and Wales, each uses its own population structure and weighting. Because these structures differ, the results from the separate calculations will not necessarily add up to the combined total.

Estimates based on sample sizes of fewer than three are suppressed in published tables, but the tables have been designed to minimise the need for suppression by combining age groups when necessary. Suppression may be needed for small groups of people, such as those in same-sex marriages in the early years following the introduction of legislation enabling same-sex couples to marry.

To help provide an understanding of the level of accuracy of the population estimates by marital status and living arrangements, the estimates in the datasets are presented with confidence intervals around the survey component of the estimate, and an indication of the size of the coefficient of variation (CV) for the survey component of the estimate. The CV indicates the robustness of each estimate. This is calculated by dividing the estimate by the standard error.

The confidence intervals and CVs are calculated to reflect the uncertainty of the survey element of statistics: the uncertainty from the population component has not been accounted for. Work around assessing this uncertainty is ongoing.

An important factor in calculating uncertainty associated with these statistics is the sample size. Response rates have been declining across surveys for a number of years. Figure 1 shows the achieved sample sizes for the dataset used in the calculation of our estimates.

If population weightings for the LFS or the mid-year population estimates are revised to reflect improvements to methods or data, then we also revise these statistics.

Statistical accreditation

The Office for Statistics Regulation independently reviewed the population estimates by marital status and living arrangements accredited official statistics in March 2017. They comply with the standards of trustworthiness, quality and value in the Code of Practice for Statistics  and should be labelled "accredited official statistics".

How we quality assure the data and statistics

1. Social Survey Division carries out validation checks as part of the production of the Labour Force Survey (LFS) dataset.

2. We carry out validation checks when we receive the dataset and apply edit rules:

• lone parents do not have a partner in the household
• no one aged under 16 years is married or living in a couple; this will be updated to reflect the Marriage and Civil Partnership (Minimum Age) Act 2022
• nobody is in a civil partnership before 2005
• children are not heads of families

3. If our validation checks fail, these cases are referred to the Social Surveys Division within the Office for National Statistics (ONS) for validation and correction.

4. Visual quality assurance is also carried out on the data; this includes checking that:

• marital status distributions are plausible by age

• there are no large year-on-year changes

• totals sum to the annual mid-year population estimates

Strengths and limitations

Strengths

• These data provide users with valuable insight into the changing patterns of marriage, civil partnership and cohabitation back to 2002.
• The mid-year population estimates are produced using a well-established demographic approach; the data sources used are the best that are available on a nationally consistent basis.
• The survey estimates are taken from the LFS, which provides survey estimates used for labour market, economic statistics and family and household statistics.
• The use of household survey estimates means that the marital status statistics are adaptive to changes in legislation relating to legal marital status (for example, the introduction of civil partnerships and same-sex marriages); however, small sample sizes may mean that it takes a number of years before it is possible to produce robust estimates at lower geographies or by other demographic characteristics such as age.
• Confidence intervals and an indication of the size of the coefficient of variation are presented around the survey component of the estimates to give users an indication of the reliability of the estimates.

Limitations

• The LFS does not include the 2% of the population living in communal establishments such as prisons and nursing homes; these residents have different marital status distributions from those in private households, which are not taken into account.
• Estimates published since July 2015 use a new methodology so are not directly comparable with the population estimates by marital status previously published by the Office for National Statistics (ONS).
• Population estimates by marital status are available for England and Wales only; no comparable figures are available for Northern Ireland, and the latest estimates available for Scotland are for mid-2008.
• International comparisons of marital status are not straightforward for a variety of reasons, including differences in the legal marital statuses available to residents, the age structure of the population affecting the proportion within each legal marital status, and differences in the way the data are collected and presented (for more detail see Comparability and coherence with other statistics producers).
• Although measures of uncertainty are provided, they only relate to the survey component and do not currently account for uncertainty surrounding the mid-year population estimates.

European Statistical System quality dimensions

The Office for National Statistics (ONS) has developed Guidelines for measuring statistical quality based on the five European Statistical System (ESS) quality dimensions. These are:

• relevance
• accuracy and reliability
• timelessness and punctuality
• comparability and coherence
• accessibility and clarity

We have integrated these considerations into the guide.

Over the years, we have changed how we produce population estimates by marital status and living arrangements. Sometimes this is to improve the statistics, and sometimes it is because of external changes (such as changes to policy, or changes to legal definitions).

Changes can sometimes affect comparability of the statistics over time.

Latest changes

We restructured and made minor updates to this guide on 15 October 2025. We have made no important changes to quality and methods. We have also started to make adjustments to our quality assurance processes following the introduction of the Marriage and Civil Partnership (Minimum Age) Act 2022.

Past changes

These changes are ordered by date, with the most recent first.

Marital status definitions

Further to provisions set out in the Civil Partnership Act 2004 and the Civil Partnership (Opposite-sex Couples) Regulations 2019, opposite-sex couples in England and Wales became eligible to form a civil partnership from 31 December 2019. Opposite-sex civil partners are included in the estimates of the population in civil partnerships for the mid-years ending 2020 onwards. Consideration will be given as to how best to incorporate opposite-sex civil partnerships in the future, dependent on the number of opposite-sex civil partners sampled as part of the Labour Force Survey (LFS).

Geography

Since July 2017, separate estimates for England and Wales have been produced. We use the existing methodology to produce estimates which are robust, reliable and useful for our users. The age bands that are presented for England and for Wales have been adjusted to ensure that sample sizes are large enough to produce statistically reliable estimates. This means that the age bands available differ from those for England and Wales as a whole. Figures can be compared by grouping the England and Wales combined age bands into the broader age bands used for the individual countries.

Measures of uncertainty

Confidence intervals and coefficients of variation were included from July 2016 onwards.

Method

This method was introduced in July 2015. As part of the release a consistent back series to 2002 was provided. The estimates from this method are not comparable estimates produced using previous methodologies.

Upcoming changes

Change in legislation

As the Marriage and Civil Partnership (Minimum Age) Act 2022 fully comes into force and eligibility rules impacting the statistics change (by 2025 it will not be feasible for anyone under the age of 18 years to be married or civil partnered), our quality assurance procedures will be updated to reflect these changes and we will seek to consider how best to approach this change in our analysis.

Reweighting following census rebase

Following the 2021 Census, the LFS will be reweighted back to 2012. Once this happens for the households dataset, we will update the statistics accordingly.

Change in data source

As part of the work to transform the LFS, we are expecting to move our survey data source to the Transformed Labour Force Survey (TLFS). Before this happens, an analysis will be conducted to ensure that it is a suitable data source to continue producing these statistics. Other data sources will also be investigated alongside this work.

There are no known statistical producers of population estimates by marital status within the UK.

For alternative population estimates of marital status and living arrangements, including lower levels of geography, please refer to Census 2021 analysis on legal partnership status and living arrangements.

A range of organisations and government departments use our population estimates by marital status and living arrangements statistics to inform services and policies. For example, the estimates:

• are used for forecasting around pensions and National Insurance funds
• are used as denominators in the calculation of rates, for example, the rate of births within marriage.
• have a number of uses, both direct and indirect, informing policy decisions at a national level

Other users include academics, researchers, charities and the media.

Marital status

A person's legal marital status:

• married

• civil partnered

• widowed (including surviving civil partner)

• divorced (including those who have been granted a dissolution of their civil partnership)

• never married or civil partnered

Separated couples are considered to be married or civil partnered (having not legally divorced or dissolved a civil partnership).

Living arrangement

Whether or not someone is living together as a couple within the same household.