Nearly half of households worldwide spend more than 30% of their income on housing, house prices have risen faster than incomes since 2010, and the tools known to help, such as social rental housing, housing allowances and zoning reform, reach too few people.
Written from the sources listed below, not independently peer-reviewed.
UN-Habitat tracks a global ratio of house prices to household incomes. Roughly what was it in 2023?
~45%
Households worldwide spending over 30% of income on housing
UN-Habitat estimate published in its SDG 11 Global Report 2026, which does not state the data year in the text. Shares are highest in sub-Saharan Africa (55%), Europe and Northern America (50%) and Latin America and the Caribbean (48%). The 30% benchmark is indicative, not a universal standard.
Data year 2026. Source: UN-Habitat, 2026
11.2
Global ratio of house prices to incomes
In 2023, up from 9.3 in 2010, according to UN-Habitat. A rising ratio means that home prices have grown faster than incomes.
Data year 2023. Source: UN-Habitat, 2026
8.2%
People in the EU overburdened by housing costs
Share of people in households spending 40% or more of disposable income on housing in 2024 (EU-SILC survey). Rates ranged from 2.4% in Cyprus to 28.9% in Greece.
Data year 2024. Source: Eurostat, 2026
Unit: ratio
The two values reported by UN-Habitat in its SDG 11 Global Report 2026; the report does not give values for the years in between. A higher ratio means house prices have risen faster than incomes.
SDG target 11.1 aims to ensure access for all to adequate, safe and affordable housing and basic services and to upgrade slums by 2030. Its indicator 11.1.1, on slums, informal settlements and inadequate housing, is the only SDG 11 indicator with enough data to estimate the distance to the target, and UN-Habitat finds that progress is limited and absolute numbers are getting worse. Affordability is also moving the wrong way: the global ratio of house prices to incomes rose from 9.3 in 2010 to 11.2 in 2023. UN-Habitat concludes that the world is still far off track for SDG 11 and that progress will take more than building new homes alone.
Housing cost burdens are heaviest in sub-Saharan Africa, where an estimated 55% of households spend more than 30% of their income on housing, compared with 50% in Europe and Northern America and 48% in Latin America and the Caribbean.
Source: UN-Habitat, 2026In Colombia, Chile, Finland, Israel and New Zealand, more than half of low-income households renting on the private market spend over 40% of their disposable income on rent. In Israel, 2% of low-income tenants in subsidised housing are overburdened, against 54% of those renting privately.
Source: OECD, 2024In the EU in 2024, 10.1% of people at risk of poverty or social exclusion said they had felt discriminated against when looking for housing, more than twice the 4.7% among people not at risk.
Source: Eurostat, 2026UN-Habitat finds that low-income households, informal workers, renters and residents without secure tenure or regular documentation are often left out of formal housing finance, while older persons, young people, refugees and migrants face some of the most acute affordability pressures.
Source: UN-Habitat, 2026Instead of one “percent solved” score, DO GOOD rates three separate dimensions. A problem can have mature solutions that still reach too few people. These ratings are an editorial reading of the sources on this page, not a measured index.
Has the situation improved in the real world?
LowNearly 45% of households worldwide spend more than 30% of their income on housing, and the global ratio of house prices to incomes rose from 9.3 in 2010 to 11.2 in 2023, so housing has become less affordable relative to incomes.
How mature and validated are the available solutions?
ModerateSeveral tools are long established: in Vienna, around 220,000 municipal flats and roughly 200,000 subsidised dwellings house about half of residents and help moderate rents. Rigorous evidence on how zoning reform and housing allowances change prices and rents comes from a small number of cities and countries.
How widely are effective solutions actually used?
LowSocial rental housing makes up about 7% of all dwellings across the OECD and less than 2% in seven member countries, and its share fell in 18 of 25 countries with comparable data over the past decade.
Survey data in the EU and OECD are detailed but use different income concepts and reference years, and consistent data on total housing costs exist only for European countries and New Zealand. Global estimates rest on an indicative 30% threshold, and UN-Habitat notes that globally representative urban data are often too infrequent.
House prices have outpaced incomes since 2010, and the share of homes let at below-market rents has fallen in most OECD countries with data, through slower construction and sales or conversions of social homes.
Housing costs are rising faster than incomes in much of the world. UN-Habitat estimates that nearly 45% of households worldwide spend more than 30% of their income on housing, with the highest shares in sub-Saharan Africa (55%), Europe and Northern America (50%) and Latin America and the Caribbean (48%). Between 2010 and 2023 the global ratio of house prices to incomes rose from 9.3 to 11.2. In many cities, demand has outpaced the supply of suitable homes, and the high cost of serviced land, together with weak municipal budgets, makes new affordable housing hard to finance. UN-Habitat links severe unaffordability in Europe, Northern America, Australia and New Zealand to rising homelessness there, and estimates that at least 3 billion people worldwide live in inadequate housing.
High costs fall hardest on people with low incomes and on tenants. In the EU, 8.2% of people lived in 2024 in households that spent 40% or more of their disposable income on housing, ranging from 2.4% in Cyprus to 28.9% in Greece. OECD data show that tenants are more likely than owners to be overburdened and that low-income households usually have the highest rates; once utilities, taxes and maintenance are counted, more than half of low-income private tenants in 17 countries spend over 40% of their disposable income on housing. Unaffordable housing also narrows choices: UN-Habitat notes that older people, young people, informal workers, refugees and migrants are among those under the most acute pressure, and that formal mortgages and public subsidies often do not reach renters, informal workers or people without secure tenure.
There is no single international measure of housing affordability. Statistical offices and UN agencies compare housing costs with income in several ways, each with its own blind spots. People without any home and people living in slums face related but different problems, covered on the homelessness and informal settlements pages:
Cost burden: more than 30% of income
A household is often called cost-burdened if it spends more than 30% of its income on housing. UN-Habitat uses this benchmark for its global estimate but stresses that it is an indicative measure, not a universal standard of affordability across regions.
Overburden: 40% or more of disposable income
Eurostat and the OECD count people as overburdened when total housing costs, net of housing allowances, reach more than 40% of disposable income, also net of allowances. For tenants, costs include rent, utilities, charges and regular maintenance; for owners, mortgage interest, insurance, taxes, maintenance and utilities.
House prices relative to incomes
The ratio of house prices to incomes shows how far buying a home has moved out of reach. UN-Habitat reports a global ratio, which rose from 9.3 in 2010 to 11.2 in 2023. An average ratio says nothing about which households can still afford to buy.
Below-market housing supply
The OECD defines social rental housing as rental homes let below market prices and allocated by specific rules rather than by the market. Its share of all dwellings shows how much of a country's housing is shielded from market rents.
What works
Social rental homes are let below market prices and allocated by set rules rather than by the market. Where the sector is large, it shields many households from market rents: Austria, Denmark and the Netherlands each have more than 20% of their housing stock in social rental housing, against an OECD average of about 7% (2022 or latest year).
Limits
The sector is shrinking in most countries with data: its share fell in 18 of 25 OECD countries over the past decade, by more than 2 percentage points in Finland, the Netherlands and Poland, because of slower construction and sales to tenants or conversion to market rentals. Colombia, Estonia, Israel, Latvia, Lithuania, Portugal and Spain have less than 2% of their stock in the sector, and national definitions and data differ.
What works
Land-use rules decide how many homes can be built on a plot. In 2016 Auckland, New Zealand, upzoned about three quarters of its residential land, allowing more homes on the same land. A peer-reviewed study comparing upzoned and other areas estimated that about 21,808 more dwellings were permitted in the following five years than would otherwise have been, roughly 4.1% of the region's housing stock; the effect was clear for attached dwellings but not for detached houses.
Limits
The study counts building permits, not completed homes, and cannot measure demolitions, so the net gain in homes is uncertain. Some construction may have shifted from areas that were not upzoned, the main analysis does not estimate effects on prices or rents, and it covers one city, so it does not show which features made the reform work or whether they would work elsewhere.
What works
Housing allowances are cash payments that help households meet rent or other housing costs, and nearly all countries target them at low incomes. In Austria, Finland, France, Ireland, the Netherlands and Sweden, more than half of households in the lowest fifth of incomes report receiving one.
Limits
Coverage varies widely: Bulgaria, Greece and the Slovak Republic have hardly any recipients. Because allowances are withdrawn as earnings rise, they can weaken the gain from working more; in Austria, almost 60% of the effective tax on extra earnings comes from losing the rent allowance. Allowances do not add homes, and definitions differ between countries.
What works
Cities can use planning powers to set land aside for affordable housing and to capture part of the rise in land values that public decisions create. Brazil's 2001 City Statute lets municipalities reserve land through Special Zones of Social Interest for affordable housing and slum upgrading, alongside national programmes that finance housing, infrastructure and land regularisation.
Limits
The scale of need remains large: Brazil's statistics office mapped 12,348 favelas and urban communities with 16.4 million residents in 656 municipalities. The high cost of serviced land and weak municipal revenue and borrowing capacity limit what many cities can finance.
Promising, but not proven at scale. The stage shows how far each approach has come; it is not a recommendation.
Instead of rezoning plot by plot, some cities now allow denser housing across most residential land at once, as Auckland did in 2016. Permits there were still rising in 2021, and the study's authors note that the full effect will not be known for several more years; evidence on rents and on other cities is still limited.
Formal mortgages, public subsidies and private investment often bypass informal settlements, rental housing and incremental self-building. UN-Habitat calls for expanding finance through subsidies, refinancing institutions, public investment and regulated social housing providers so that it reaches low-income households, informal workers and renters; how to do this at scale is still being worked out.
Measures based only on rent or mortgage payments understate the burden. When the OECD adds utilities, taxes and maintenance, more than half of low-income private tenants in 17 countries spend over 40% of their disposable income on housing. Consistent data on these total costs exist so far only for European countries and New Zealand.
Implementation gap
The high cost of serviced land, combined with weak municipal revenue and borrowing capacity, widens the financing gap for affordable homes, especially in fast-growing cities where demand already outpaces suitable supply.
Implementation gap
The share of social rental housing fell in 18 of 25 OECD countries with comparable data over the past decade, as new construction slowed and homes were sold to tenants or converted to market rentals. Each home lost has to be replaced before the sector can grow.
Coordination gap
Where zoning caps how many homes can go on a plot, new supply is held back. Auckland's experience suggests these limits can be binding: after the city upzoned about three quarters of its residential land, an estimated 21,808 additional dwellings were permitted within five years.
Implementation gap
Formal mortgage markets, public subsidies and private investment often fail to reach informal settlements, rental housing and incremental self-construction, leaving out low-income households, informal workers, renters and people without secure tenure or documentation.
Coordination gap
Housing allowances are withdrawn as income rises, which interacts with taxes and other benefits. In Austria, almost 60% of the marginal effective tax rate comes from losing the rent allowance, and in Finland, Norway and Sweden the share exceeds 40%, so housing and tax-benefit policies need to be designed together.
Knowledge gap
Countries measure income differently, some using gross rather than disposable income, survey years differ, and small samples make year-to-year changes uncertain. Consistent total housing cost data exist only for European countries and New Zealand, and outside the OECD most estimates rely on an indicative 30% threshold.
Unresolved questions, not vetted breakthroughs. Answering any of them would change what is possible.
Allowing more homes increased construction in Auckland, but how much do such reforms lower rents and prices, for which households, and how quickly in cities with different land markets and building industries?
How much of a housing allowance ends up with tenants rather than landlords as higher rents, and how does this depend on how tight the local rental market is?
Can a comparable affordability measure, beyond a fixed 30% threshold, be built for low- and middle-income countries where many people rent informally or build their own homes in stages?
Which ownership, finance and allocation models keep below-market homes affordable for decades rather than losing them to sales and conversions, and can they work in countries without a long tradition of social housing?
Proposals for new homes, denser neighbourhoods or affordable housing are often decided at local planning meetings. Reading the plans and adding a comment in support or with constructive concerns is one way to be heard.
Find out which housing allowances, social housing waiting lists and tenant advice services exist where you live. Passing this on to a neighbour, colleague or relative who is struggling with rent can help them claim support they are entitled to.
Before local or national elections, ask candidates how they plan to increase the supply of homes that people on low incomes can afford, and how they will measure whether it worked.
If you donate or invest, choose housing associations, cooperatives or charities that publish how many homes they provide, what rents they charge relative to local incomes and who lives in them.
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UN-Habitat, published 2026
UN-Habitat's 2026 report on SDG 11: share of households worldwide and by region spending over 30% of income on housing, global house-price-to-income ratio (2010 and 2023), at least 3 billion people in inadequate housing, status of indicator 11.1.1, groups most affected, the Vienna public housing example, Brazil's Special Zones of Social Interest, and gaps in housing finance and land.
Eurostat, published 2026
Eurostat article dated January 2026 with EU-SILC data for 2024: housing cost overburden rate in the EU (8.2%) and by country, tenure status, overcrowding, discrimination when looking for housing by poverty status, and definitions of housing costs.
OECD, published 2024
OECD indicator sheet last updated April 2024 (data mostly 2022): housing cost burdens and overburden rates by tenure and income, low-income private and subsidised tenants, total housing costs including utilities, and comparability caveats.
OECD, published 2025
OECD indicator sheet last updated 24 November 2025: social rental housing as a share of all dwellings (about 7% across the OECD, 2022 or latest year), countries with large and very small sectors, changes over the past decade and their causes, definition and data gaps.
OECD, published 2025
OECD indicator sheet (October 2025 update): share of low- and middle-income households receiving housing allowances, payment rates from OECD tax-benefit models, effects on marginal effective tax rates, and comparability caveats.
Journal of Urban Economics 136:103555 (Greenaway-McGrevy and Phillips; author version via Cowles Foundation, Yale), published 2023
Peer-reviewed difference-in-differences study of Auckland's 2016 upzoning of about three quarters of residential land: about 21,808 additional dwellings permitted over five years (about 4.11% of the regional stock), effects by dwelling type, and limitations including spillovers, permits versus completions and the single-city setting.
DO GOOD International (2026). Affordable Homes for All. Global Challenges. Updated October 15, 2026. https://www.dogood.world/challenges/housing-affordability
For figures, please cite the original sources listed above.