Of 1167 published entries in this atlas, 236 state a cost and 931 do not. Every figure below is the one its own entry states, taken from that entry’s own sources.

Disclosure is not evenly distributed across the record: 32% of energy entries carry a figure, against 5% of society entries. A handful of entries state explicitly that the programme cost was never published.

✔ Every published entry is checked against the public sources it cites before publication.

The ten largest disclosed costs

Read this as a ranking of disclosure, not of spending. Every figure is the one its own entry states, converted at a single reference date (2026-08-07) purely so the rows can be sorted; the original figure stands beside it. The bases differ and are named in the last column, because a construction contract, a thirty-year operating contract and three decades of nominal programme spending are not the same quantity. Conversions use one reference date so the ranking is reproducible. They are approximations: several of these figures are nominal totals spread across decades, and no inflation adjustment is applied. The stated original-currency figure is always shown next to the converted one.

What was left out of the ranking, and why

• PlanIT Valley — ≈$19 billion planned total investment · The largest number in the whole cost dataset, and it was never raised. PlanIT Valley was cancelled. Ranking announced money as spending is exactly the error this page is about.
• Santiago's Suspended Smart Electricity Meter Rollout — about US$1,000M projected nationwide · A nationwide projection, not the city's spending, for a rollout that was suspended. Neither the scope nor the status fits a ranking of what cities have spent.
• Masdar City — US$22bn announced in 2008, revised down to $16bn during 2010 · The largest figure of the three revisions was never an account of spending, and only a fraction of the masterplan was built. What the two cuts do show is where the money went: the savings came from deleting the raised podium, rooftop solar on every building and the driverless pod network — the features the city was announced for.
• Nusantara — Smart Forest Capital — Rp 466 trillion (≈US$33bn) provisional requirement, 2022 · A requirement stated by the president at the groundbreaking, of which he expected four fifths to come from private and state-enterprise money that has largely not arrived. The comparable figure is the state budget actually spent — Rp 72.3 trillion (≈$4.4bn) from 2022 to May 2024 — and a plan and an outlay do not belong in the same column.

Large entries that state no cost

The ranking above can only cover entries that published a figure. The following are among the largest developments in the atlas by scope — cities built from scratch, flagship districts, a port rebuilt end to end — and none carries a cost figure in its record:

• The Line — 🇸🇦 NEOM, since 2021
• Songdo International Business District — 🇰🇷 Incheon, since 2003
• Sidewalk Toronto (Quayside) — 🇨🇦 Toronto, 2017–2020
• Tengah Forest Town — 🇸🇬 Singapore, since 2016

This page reports the coverage and stops there. What follows from it — whether the entries that disclose nothing are also the most expensive, and what may and may not be concluded from their silence — is argued separately in The Price Nobody Publishes.

Common questions

How many smart city projects publish their costs?

In this atlas, 236 of 1167 published entries carry a cost figure — 20.2 percent. Disclosure is uneven: 32 percent of energy entries carry a figure against 5 percent of society entries.

What does the cost figure on a project page cover?

It varies, which is why the ranking names the basis for every row. Some figures are construction contracts, some bundle decades of operation and maintenance, some are nominal programme totals spread across thirty years, and some are annual subsidies or per-unit prices. Cairo's monorail is reported at ≈€2.7bn for construction and ≈$4.5bn for a contract that includes thirty years of operation — the same asset, different questions. Comparing such figures without naming the basis would put different quantities in the same column.

Which large smart city projects do not publish a cost?

Fewer than when this page was written. Among the largest developments in this atlas by scope, NEOM's The Line, Songdo, Sidewalk Toronto's Quayside and Singapore's Tengah district still carry no cost figure at all. Three others were checked at source in August 2026 and now do: Shanghai's Yangshan Phase IV terminal (an investment approved by the national regulator), Indonesia's new capital Nusantara (a provisional requirement stated by the president) and Masdar City (an announced budget, twice revised down). None of the three is an account of what was spent, which is the distinction this page keeps in its last column.

Where to read next

The Price Nobody Publishes is the essay built on these numbers. The failure record is this page’s natural companion: several of the entries ranked above are also in it. The State of the Evidence asks the same question about proof that this page asks about money.