Draft, not yet released. In stewardship review. Not indexed until the first approved release.

Executive summary

The edition on a few pages: the abstract, the key messages, the headline finding and what each steward reads in it.

6 min read1 figure0 tables12 notesNR-SECTOR-CITIES-GLOBAL-2026-BASELINE

Contents
  1. ·Edition home
  2. ·Executive summary
    1. S.1 Abstract
    2. S.2 Key messages
    3. S.3 Headline finding
    4. S.4 At a glance
    5. S.5 What each steward reads in it
    6. S.6 What this edition is, and is not
  3. 1Cities are where the systems meet
  4. 2Key findings
  5. 3Systems and sectors at baseline
  6. 4Risks and capability
  7. 5Heat wave followed by flooding in a subsiding coastal city
  8. 6Readings from the other desks
  9. 7The 2027 agenda
  10. 8Systems in depth
  11. AMethodology
  12. BData appendix
  13. CReferences and record
  14. ·Complete edition, for print

S.1Abstract

The world enters 2027 with cities that are larger, more numerous and more exposed than the statistics of a decade ago suggest. The United Nations Population Division now counts 45% of the world’s 8.2 billion people as living in cities on a harmonised grid-based definition, while the World Bank series, built on national definitions, shows 57.8% urban in 202512. Both are reported here with their issuers because they measure different things. There were 33 megacities in 2025, against 8 in 1975, but 96% of the more than 12,000 cities analysed have fewer than 1 million people1. Housing is the clearest gap: 1.12 billion people lived in slums or informal settlements in 2022, 24.8% of the urban population5. Urban areas produced about 29 GtCO2-eq in 2020, 67 to 72% of the global share on a consumption basis6. Heat and flood concentrate in cities: urban exposure to extreme heat rose by nearly 200% between 1983 and 2016, and 1.81 billion people are exposed to a 1-in-100-year flood1314. Subnational governments carry 39.5% of public investment, yet cities receive less than 20% of the finance needed for climate action2212. Green space is thin where it is most needed17. This baseline sets out what the evidence supports and where it is thin. It ranks no city and recommends no policy.

S.2Key messages

Six readings that frame the cities baseline, and the eight questions this edition answers, each with its status and source.

  1. It depends on the definition: 45% in cities on the UN grid method, 57.8% on national definitions.12

    How urban is the world?Reported

  2. Two thirds of growth to 2050 is in cities, mostly small and medium ones in Asia and Africa.17

    Where is growth?Reported

  3. About 1.12 billion people live in slums or informal settlements.5

    Who lacks adequate housing?Reported

  4. About 29 GtCO2-eq in 2020 on a consumption basis, 67 to 72% of the global share.6

    How much do cities emit?Reported

  5. Urban heat exposure rose nearly 200% in 34 years; 1.81 billion people face a 1-in-100-year flood.1413

    How hot and how wet is the risk?Reported

  6. Subnational governments make 39.5% of public investment; cities receive less than 20% of climate finance need.2212

    Who pays for urban resilience?Reported

  7. Tree cover offsets 41 to 49% of the potential heat island but is thin in low-income cities.1517

    Can green cover help?Reported

  8. A heat wave followed by flooding in a subsiding coastal city. SCN-GS10-HTF-01

    What will 2027 test first?Expert input

S.3Headline finding

ReportedEQL 4NRF-SECTOR-CITIES-GLOBAL-2026-BASELINE-HLT-004

About 1.12 billion people lived in slums or informal settlements in 2022, 24.8% of the urban population.

Figure S.1Urban population in slums or informal settlements (%)
ItemBar, scaled to the largest valueValue
UN SDG database, 202224.8
World Bank series, 202223.2
UN SDG database, 201525.3

Sources: UN SDG database3 and Goal 11 page5; World Bank World Development Indicators2. The share fell slowly while the number rose.

The share barely moved between 2015 and 2022, so the number rose by about 130 million. Informal settlements are also the places least covered by adaptation plans, and the UN expects Sub-Saharan Africa to add 360 million slum residents by 2030512.

S.4At a glance

45%

of people in cities, 20251

33megacities

in 2025, from 8 in 19751

24.8%

of urban people in slums, 20223

29GtCO2-eq

urban emissions, 20206

1.81billion

exposed to a 1-in-100-year flood13

39.5%

subnational share of public investment22

S.5What each steward reads in it

GCRI · KEY T

Technical Truth

The evidence supports reading cities as the place where systems meet.

GRF · KEY M

Public Meaning

For most people urban risk arrives as a hot night, a flooded street or a missing service.

GRA · KEY F

Capital Meaning

Readiness implications only. Municipal finance is short of need and subnational governments carry a large share of public investment.

NEXUS

Synthesis

Cities are well measured at the level of population and emissions, and thinly measured at the level of services, plans in force and losses.

S.6What this edition is, and is not

What this edition is

A baseline: the 2026 state of the world’s cities and urban systems and the couplings through which it carries risk into other systems. It synthesises published evidence and ranks no country, company or asset.

What it is not

Not a ranking of cities, a forecast of population or property values, a planning recommendation or an assessment of any municipality, mayor or government. Urban planning, land use and services rest with local and national authorities.

What comes next

National, regional and sector evidence feeds the 2027 cities edition through the federation. Each edition reports what changed against this baseline: observations, source revisions, method changes, scenario updates and corrections.

Notes

Numbers are the edition’s reference numbers, so a note reads the same in every chapter. The full list, with every source and its licence, is in Annex C. Annex C, references

  1. 1UN DESA Population Division (ed.), World Urbanization Prospects 2025: Summary of Results (publication page and press release; 45% of 8.2 billion people in cities, 33 megacities, more than 12,000 cities, Degree of Urbanisation). United Nations, New York, November 2025. Observation year 2025. Accessed 2026-11-03.back
  2. 2DATA VINTAGE AFTER CLOSE: World Bank (ed.), World Development Indicators, API extract of urban population, total population, urban agglomerations, urban access to electricity, clean cooking, safely managed drinking water and sanitation, slum share (database updated 8 October 2026). World Bank, Washington. Observation year 2025 (population) and 2024 (access). Accessed 2026-11-03.back
  3. 5UN DESA (ed.), Sustainable Development Goal 11: make cities and human settlements inclusive, safe, resilient and sustainable (Goal page; slum population, land consumption rate, targets). United Nations, New York. Observation year 2022 (slums) and 2025 (land consumption). Accessed 2026-11-03.back
  4. 6IPCC (ed.), Urban systems and other settlements, chapter 8 in Climate Change 2022: Mitigation of Climate Change, Contribution of Working Group III to the Sixth Assessment Report of the IPCC (downloaded chapter, executive summary read). IPCC, Geneva, 2022. Observation year 2020. Accessed 2026-11-03.back
  5. 13Rentschler, J., Salhab, M. and Jafino, B.A., Flood exposure and poverty in 188 countries, Nature Communications 13, 3527 (open access full text, PMC). Springer Nature, London, 2022. Observation year 2020 (population grid). Accessed 2026-11-03.back
  6. 14Tuholske, C. et al., Global urban population exposure to extreme heat, Proceedings of the National Academy of Sciences 118(41), e2024792118 (open access full text, PMC). National Academy of Sciences, Washington, 2021. Observation year 2016 (series 1983 to 2016). Accessed 2026-11-03.back
  7. 22OECD and UCLG (eds.), World Observatory on Subnational Government Finance and Investment, 2022 highlights (135 countries; 2020 data). Organisation for Economic Co-operation and Development, Paris, and United Cities and Local Governments, Barcelona. Observation year 2020. Accessed 2026-11-03.back
  8. 12UN-Habitat (ed.), World Cities Report 2024: Cities and Climate Action, key messages (report page; cities receive less than 20% of climate finance needed). United Nations Human Settlements Programme, Nairobi. Observation year 2024. Accessed 2026-11-03.back
  9. 17Romanello, M. et al., The 2023 report of the Lancet Countdown on health and climate change: the imperative for a health-centred response in a world facing irreversible harms, The Lancet 402 (open access full text, PMC). Elsevier, London, 2023. Observation year 2022. Accessed 2026-11-03.back
  10. 7IPCC (ed.), Cities, settlements and key infrastructure, chapter 6 in Climate Change 2022: Impacts, Adaptation and Vulnerability, Contribution of Working Group II to the Sixth Assessment Report of the IPCC (downloaded chapter, executive summary read). IPCC, Geneva, 2022. Observation year 2020. Accessed 2026-11-03.back
  11. 15Trees halve the urban heat island effect globally but unequal benefits only modestly mitigate climate-change warming, Nature Communications (2026), open access full text, PMC. Springer Nature, London. Observation year 2026 (analysis of 8,919 large urban areas). Accessed 2026-11-03.back
  12. 3UN Statistics Division (ed.), Global SDG Indicators Database, API extract of series EN_LND_SLUM, EN_ATM_PM25, EN_ACS_URB_OPENSP, SP_TRN_PUBL, EN_REF_WASCOL and SD_CPA_UPRDP (release 2026.Q3.G.01). United Nations, New York. Observation year 2024 (slums), 2023 (PM2.5) and 2020 (transport, open space). Accessed 2026-11-03.back

Cite this summary

Valadbaygi, S. (Ed.). (2026). Executive summary: Executive summary. In Global Cities Risk and Resilience Report 2026: Baseline Edition, The State of the World’s Cities and Urban Systems. (Baseline Edition 2026, Report No. NR-SECTOR-CITIES-GLOBAL-2026-BASELINE) [Draft under review]. The Global Centre for Risk and Innovation (GCRI).

Every citation form of the whole report, BibTeX and RIS included, is on the edition home. Cite this report

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Sector signature

The sectors behind Global Cities and Urban Systems.

A reading aid: the sectors the findings run through and how strongly they depend on each other.

Select corners · hover lines6 / 15 relations

Context

Infrastructure and its partners

Infrastructure gives pipes, dams and treatment works to water (0.6), transmission and fuel logistics to energy (0.6) and access to care to health (0.5).

W · E · I · F · H · B

Sectors
4 of 6
Relations
6 of 15
Coupling
0.46 share of total

Strongest relations in play

  • Energy → Infrastructure · power for transport and telecoms0.8
  • Water → Energy · cooling water and hydropower0.6
  • Infrastructure → Water · pipes, dams and treatment works0.6
  • Water → Health · drinking water and sanitation0.7
Teaching values for a typical city-region, not measurements for any place. Coupling is the summed strength of the relations in play, as a share of all fifteen.
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