A two-year-old unit tasked with taxing Tanzania's wealthiest visited Skatteforsk — Norwegian Centre for Tax Research in search of tools to see the fortunes that hide offshore. This is a dispatch on what it takes to make a hidden economy visible, and why a country's largest fiscal ambition may turn on it.
Ten officials sat around the table at Skatteforsk, the Norwegian Centre for Tax Research at NMBU, on 7 October 2026. They had come from Dar es Salaam, from a unit of the Tanzania Revenue Authority created barely two years ago to do one thing: tax the country's wealthiest individuals.
In its first twelve months the unit registered just over a hundred of them and collected about 14 billion Tanzanian shillings — 75% above its own target, but a rounding error against the task behind it.
That task is the largest fiscal ambition in Tanzania's modern history. The country's new long-term plan intends to raise annual tax revenue from roughly 10 billion US dollars today toward something close to 140 billion by 2050. A small and recent unit of the Tanzania Revenue Authority had travelled to a modest Norwegian university town to look for tools adequate to the largest horizon.
This is a dispatch from the researchers on the other side of that table.
The 2050 vision challenges the hidden economy
Every tax system sees some of the economy clearly and the rest only in outline. In Tanzania, around 91% of all personal income tax is collected through Pay As You Earn — the channel that withholds tax from salaries before the wage is ever paid. Formal employment often supplies more than nine-tenths of personal income tax across the administrations the African Tax Administration Forum has studied; Tanzania is a typical case. That is the visible economy: formal, salaried, captured at source. It is also the easiest to overtax, because it is the easiest to reach. The barely one-tenth collected from anywhere else is a mixed remainder — the modest sums that self-employed traders and small enterprises do file, alongside the capital gains, dividends and rents that accrue above all to wealthy individuals. It is at the far edge of that thin, loosely captured band that the income of the affluent begins to disappear from view.
Beyond the edge lies the hidden economy, a part of which is hidden by design. The companies that wealthy individuals control, the property they hold, the financial assets they move offshore: these sit across land registries, company records, and foreign accounts that for many tax systems are out of reach. The high-net-worth unit of the Tanzania Revenue Authority exists to make that second economy visible.
The financial stakes of the Tanzanian state are challenging, which is why a Presidential Tax Reform Commission has proposed 284 measures to modernise collection. Tanzania's tax-to-GDP ratio sits around 13% — well below the sub-Saharan African average near 18%. Moving from about 13% of GDP to at least 25% by 2050 means almost doubling the tax collected per unit of output. The ratio has to rise by roughly 2.5% a year, compounded, for a quarter of a century. With real growth near 6%, real tax revenue would have to grow close to 9% a year, every year, for twenty-five years. Growth alone cannot do it: if tax rises only as fast as GDP, the ratio never moves. Tax revenue has to systematically outrun the economy. In this context, taxing the wealthy is no longer an abstraction or a slogan. It is a budgeted, politically backed priority, and the unit is its sharp end.
It has to do so, moreover, without the supports that used to absorb the shortfall. Tanzania's IMF programme — the concessional arrangement in place since 2022 — reached its final reviews in mid-2026. The 2026/27 budget projects domestic revenue covering roughly three-quarters of spending, with the aid share falling below 1%. This is a deliberate pivot toward self-reliance, and it removes the external anchor at exactly the moment the revenue target becomes most demanding. That is the pressure the delegation carried into the small NMBU room.
What the unit came for
The questions they brought were concrete: how much wealth is held abroad by high-net-worth individuals in the form of real estate? An apartment in Dubai Marina held by a wealthy Tanzanian resident can be invisible to the unit. This is because cities like Dubai and other tax havens conceal who really owns what — the beneficial owner behind a property. If the property is held through a company — often registered somewhere else — it will be the company, not the person, that any record shows. The profile the Tanzanian unit can build stops at the border.
This is the gap the Atlas of the Offshore World was built to close. Produced by Skatteforsk together with the International Tax Observatory in Paris, the Atlas is a free, public effort to measure the wealth that escapes national tax authorities — money hidden in offshore accounts, profits shifted by multinationals, and property held abroad. The Atlas begins exactly where the unit's profile stops, and its method is a look-through: the team does not start from what an owner declares; it starts from the property. For each market it assembles a registry of residential properties and their nominal owners from official cadastral data where it is published. Those registries give the property and its value — Dubai, for one, does publish them — but rarely the residence of the owner behind it, so the team turns to leaked records to establish who the owner is and where they live. Then it follows the ownership chain. Where a property is held by a company, the aim is to trace that company to the beneficial owner and to assign that person a country of residence. Most jurisdictions still do not record the beneficial owners of the foreign companies that hold real estate on their soil; where a public register does — like the United Kingdom's Register of Overseas Entities — the team can use it, and elsewhere it relies on leaked records. A villa that a French registry files under a Luxembourg holding company, the Atlas files under the person behind the company. A Dubai apartment held through a shell, it files under the Dar es Salaam resident who owns the shell: this is the type of information that specialized units in tax administrations are interested in.
The look-through is only one of the Atlas's methods. For a country like Tanzania, outside the OECD's automatic-exchange network, it also reconstructs offshore financial wealth indirectly — from international banking statistics and national accounts — reaching an estimate where the administration's own records go dark.
Havens of peace and havens of secrecy
The yield of the high-net-worth unit will stay modest. The most optimistic domestic estimates put the additional revenue at a few tens of billions of shillings a year, a low single-digit share of the annual effort the 2050 path requires. But the unit's real value is as an opener. Profiling one wealthy individual exposes the companies they control, the rents they collect, the property they hold, the public contracts they win, the assets they keep abroad. Each of those is a separate tax base, weakly captured today. The unit is best understood not as a small specialist programme but as a high-value testing ground for an integrated fiscal-intelligence system — one that assembles unique taxpayer identifiers, beneficial-ownership data, linked land, company and customs records, and cross-border information. Build that for a hundred wealthy individuals and it serves the whole system.
Before they left, the delegation brought a gift: a wooden plate carved with the port of Dar es Salaam. There is a quiet joke in it. A centre that spends its days estimating the wealth hidden in tax havens was handed a carving of a harbour, from the city whose name, in Arabic, means haven of peace. And a port is the right emblem for the encounter. For the bird's eye view depicted on the plate, everything is visible: the cranes, the berths, the declared cargo moving through the haven of peace, and the customs post built to count it. What the carving cannot show is the value that also leaves — through ownership chains, offshore accounts and declarations never made, past a customs post that was never built for it.
That second flow is the economy the unit wants to unveil. The unit that visited Skatteforsk is small — ten officials, a hundred names on a list — and the room behind the door is the entire 2050 project: a state learning to see, and then to tax, an economy built to stay out of view. That a slight instrument should come so far north in search of tools for such large a horizon is the whole measure of what is at stake. The door is open.