Sovereign debt: maturity walls, rate scenarios and who buys the debt

How much government bond and bill debt eleven major economies must repay, and in practice refinance, in the coming months and years; what a change in inflation or interest rates does to the interest bill; who buys the debt; and the long view of the United States.

Maturity wall: how to read it

What is counted

The amounts are principal coming due on marketable central-government securities (bills, notes and bonds) that exist at each country's data date. Interest payments are not included.
A government rarely repays this money out of its budget: it usually issues new securities to pay back the old ones. "Coming due" therefore reads as "to be refinanced at the yields of that day".
Debt as a share of GDP here is marketable central-government debt only, so it is lower than the general-government ratios usually quoted. GDP is each country's latest full-year figure.

The three units

US dollars: every amount converted at the exchange rates of 13 Oct 2026. Useful to compare sizes.
% of GDP: every amount as a share of that country's yearly GDP. Useful to compare weight.
Local currency: only for one country at a time. The ranking and the table by year then stay in US dollars, because amounts in different currencies cannot be compared.

Due in the next 12 months

One bar per country, split into bonds & notes and bills. Bills are short paper (a few weeks to a year) that is repaid and issued again several times a year, so a country that funds itself with many bills shows a large 12-month amount. A grey bar means only the total is known, not the split.

Repayments by year

"Oct–Dec 26" is only what is left of the year in progress, not a full year.
The last column, "2036+", is everything due in 2036 or later in one lump. It is not comparable with a single year, so it is left unshaded.
The shading compares the cells with each other. In US dollars it uses a square-root scale, so that smaller economies stay visible next to the largest one; in % of GDP it is a plain scale.
A figure with \* is an estimate. A hatched cell means no schedule is published.
The dot before a name is the quality of that country's figures: full green = official figures, amber = partly estimated, a red ring = incomplete.

Country detail

By calendar year: the same eleven buckets as the table, bonds & notes and bills stacked. The last, hatched bar is the lump of all later years.
By month: only securities that already exist. Bills issued after the data date that also come due inside the window are not counted, so the bill amounts thin out in the later months even though governments keep rolling them.
A hatched series is an estimated split: the total is known, its split between months (or between bills and bonds) is derived from a pattern.
Average time to maturity is the average number of years until the debt comes due, weighted by amount. The shorter it is, the faster the debt is refinanced.

How fast the debt reprices

Each line adds up what has come due by the end of each year, as a share of today's debt. A line that climbs fast belongs to a country whose debt is replaced quickly: a change in interest rates reaches what it pays sooner. The chart says nothing about the level of the yields, only about the speed.

What differs between countries

Inflation-linked bonds are counted with their inflation-adjusted principal for the United States, Canada, the United Kingdom, France, Italy and Mexico, and at face value for Germany.
Brazil covers domestic federal securities held by the market, at their accrued value; it issues no bills.
China covers central-government bonds only; local-government bonds are not included, and no year-by-year schedule is published.
Mexico covers the federal government's own securities at the amount repaid at maturity; securities placed for the central bank's monetary regulation and external debt are not included.
Data dates differ by a few weeks between countries; each country shows its own date, and "About this data" under each country says what its figures are.

Educational tool only, not financial, economic, or policy advice. This data and content might be wrong and explains displayed metrics and model outputs and does not provide recommendations. Past patterns do not guarantee future results. Verify all information independently before relying on it.

Scenarios: what the lab computes

The idea

The lab runs one small model, year by year, for the nine calendar years after the current one. It answers a narrow question: if inflation, interest rates, the budget or the central bank's bond holdings took another path, what would the arithmetic of the debt give? It is a simplified, illustrative model, not a forecast.

How the model works

Old debt runs off on its real schedule. The debt that exists today comes due year by year as the maturity wall shows, and until then it keeps its current average cost.
New debt is financed at the scenario yield. Everything that replaces maturing debt, plus each year's deficit, is borrowed at the market yield of that year.
The market yield starts from today's refinancing yield: the average of a short yield (two years, or one year where that is the reference) and the 10-year yield. The rate slider moves it. If yields follow inflation, the inflation slider moves it one for one as well. The supply effect is added on top (below).
Inflation-linked debt costs more, one for one, with inflation above the target. Floating-rate debt reprices at once when yields move. Each country has its own shares of both.
GDP grows with projected medium-term real growth plus the scenario's inflation. Higher inflation therefore makes the economy larger in money terms, which lowers a debt ratio, while it raises the cost of new and linked debt.
The primary balance (the budget before interest) is held as a fixed share of GDP; the budget slider shifts it.
Exchange rates stay where they are today.
"Today" in the lab (the debt ratio and the interest bill it starts from) is measured against the current year's projected GDP, the footing the nine-year path starts on. The other tabs divide by the latest full year's GDP, so their ratios are slightly higher for a growing economy.
Countries without a full maturity schedule cannot be run and are left out.

The central bank and the supply effect

The central bank changes its holdings by a share of GDP each year: positive when it buys, negative when it sheds bonds. It keeps that pace until the year chosen, then its holdings stay flat. Its holdings cannot fall below zero.
Private and foreign investors must absorb the rest: the new debt issued minus what the central bank buys (or plus what it sheds).
The supply effect: when privately held debt grows faster than the economy, investors are assumed to ask a little more yield. The slider sets how much, in basis points for every point of GDP held above today's level. Set it to 0 to switch the effect off. It applies to the baseline and to the scenario alike.
Needed to hold supply pressure flat is the central bank buying that would keep privately held debt at today's share of GDP.

The baseline and the scenario

The baseline (grey, dashed) keeps inflation at the central bank's target, market yields where they are today, and the central bank's current pace.
The scenario (coloured) is what the sliders say. "Reset to baseline" puts the inflation, rate and budget sliders back to zero and the central bank's pace back to its current stance.
The supply effect, "bond yields follow inflation" and the year the central bank keeps its pace until change the baseline and the scenario together.

The charts

Interest paid per year and Who has to buy the new debt follow the unit chosen in the page head. Debt: face value vs today's money is an amount, so with "% of GDP" it is shown in US dollars.
In today's money removes the scenario's inflation from the face value: what the debt would be worth at today's prices.
Interest cost for every country applies the inflation, rate and budget sliders to every country that can be run. The pace slider moves no row of that list: every country keeps its own central bank stance, the selected one too, so its row can differ from the headline figure when the pace slider is moved.
The 10-year yields since 2006 are monthly averages of market yields. They are the background, not part of the model.

What the model leaves out

It has no recession, no change in tax receipts with growth, no market panic and no reaction of the central bank's policy rate to inflation. Rates, inflation and the budget move only as the sliders say. Small differences between two paths grow over nine years, so the far end of every line is the least certain.

Who buys & backstop: how the flags, the scores and the charts are built

An educational tool, not financial advice. This tab describes figures and rules of thumb. The flags and the two scores are prompts for a closer look and a way to compare countries: not probabilities, not a rating and not a forecast.

The squeeze watch

One row per country, largest debt first (converted to US dollars). Every figure is for marketable central-government debt.

Marketable debt and due in 12 months are shown as a share of the latest full-year GDP.
Interest now is the average cost of the debt times the debt, as a share of GDP. Where the average cost is an estimate the figure is marked *est.*
Today's yield minus average cost compares what new borrowing costs (the average of a short and a 10-year yield) with what the existing debt costs on average. A positive gap means the interest bill rises as old debt is replaced.
Central bank holds, foreign holders and foreign-currency debt are shares of the debt, set by hand from published figures and reviewed regularly; central bank today is the policy rate and what the central bank is doing with its bond holdings.

A full dot marks a value past a common rule-of-thumb threshold; a ring marks a value close to it:

| Figure | Full dot | Ring | |---|---|---| | Due within 12 months | above 15% of GDP | above 12% | | Average maturity | under 6 years | under 7 years | | Interest now | above 3% of GDP | above 2.5% | | Today's yield minus average cost | above 1 point | above 0.5 point | | Foreign holders | above 30% | above 25% | | Foreign-currency debt | above 10% | above 5% |

The thresholds are conventions, not laws: a country can sit past several of them for years.

The two scores

Squeeze pressure adds six parts, each worth 0, 1 or 2, and scales the sum to 0–10:

| Part | 2 points | 1 point | |---|---|---| | Marketable debt | over 100% of GDP | over 70% | | Due within 12 months | over 15% of GDP | over 8% | | Average maturity | under 6 years | under 8 years | | Interest now | over 3% of GDP | over 2% | | Projected deficit | over 6% of GDP | over 3% | | Buyer gap | two of the three below | one of the three below |

The buyer gap counts one point each for a central bank that is shrinking its bond holdings, foreign holders above 30% and foreign-currency debt above 10%, and never more than 2. A missing figure counts as 1, the middle value; in the buyer gap a missing share adds nothing.

Backstop strength adds five parts, each 0, 1 or 2 (0–10 in total): whether the country borrows in a currency its own central bank issues; the tools ready to buy or lend against government bonds; inflation room (latest inflation no more than 0.5 point above target = 2, no more than 1.5 above = 1; inflation below target counts as 2, an unknown rate as 1); the track record of stepping in since 2008; and how deep and captive domestic demand is. Only inflation room is computed; the other four are judgement calls, set by hand and shown in the scorecard so they can be questioned.

The small digits under each score are its parts, in this order. Pressure: debt · due in 12 months · average maturity · interest · deficit · buyer gap. Backstop: own currency · tools · inflation room · track record · domestic demand.

Simplifications. Every part weighs the same. Thresholds are steps, so two countries just either side of one differ by a full point. The scores look at the central government only and say nothing about banks, households or local governments. "What the record suggests" summarises what each central bank has done before; it is not a statement about what it will do.

The charts (United States)

Who bought the new debt each year — the change in the debt held by the public from one year-end to the next, split into the part taken by the central bank, by foreign investors and by everyone else in the United States (banks, funds, households: what is left after the first two). Below zero means a group sold or let its holdings mature. The running year covers only the quarters published so far.
The balance sheet and the plumbing — month-end levels of the Federal Reserve's total assets and Treasury holdings, the reserves banks keep there, the cash parked in its overnight reverse-repo facility (monthly average) and the Treasury's cash account. When the central bank buys bonds, reserves rise; when it lets them run off, reserves or the reverse-repo pile fall.
Term premium — a model estimate of the extra yield investors ask for holding a 10-year bond instead of rolling short ones, next to the 10-year minus 2-year yield. A model estimate is uncertain; its direction says more than its level.
Overnight funding pressure — the secured overnight rate (SOFR) minus the rate paid on reserves, in basis points: the highest day of each month and the month's average. A gap that stays above zero means cash is getting scarce in the repo market. When a month goes far above the others, the axis is cut so the ordinary months stay readable, and that month is marked with its value.
Central bank balance sheets — total assets as a share of the annual GDP of the same quarter, for three central banks. The others are not shown.

The dotted lines on the charts mark dates of central-bank decisions (the start and end of balance-sheet reduction, the 2020 purchases).

Interventions since 2008

A hand-kept list of episodes of government-bond stress and what the central bank did, including the episodes where it did not buy. Sizes and inflation rates marked ≈ are approximate.

US long view & money: how the series are built

These charts describe what happened up to the latest figures; they say nothing about what comes next.

Yearly values

Every series is shown once a year, over the whole history available.

Stocks (the debt and who holds it, M0, M1, M2) are fourth-quarter values: the level at the end of the year.
Flows and rates (interest paid, GDP, the 10-year yield, the Fed funds rate, velocity) are the average of the year's four quarters. Inflation is the rise of the year's average price level over the year before.
The running year is partial. A stock shows the latest quarter published; a flow or a rate averages the quarters published so far. It is drawn as a hollow dot, the hover names its quarters, and each chart's note under it lists them. Series are published at different speeds, so their last quarters can differ.

What the series are

Total federal debt is all debt owed by the federal government, including what one part of the government owes another (such as the trust funds), so it is larger than the debt held by the public.
Held by foreign investors is the part owned by foreign and international holders; held by the Fed is the Treasury securities on the Fed's balance sheet. Each line starts when its record begins.
Interest paid is the federal government's interest expense, as an annual rate. Its share of GDP divides it by the size of the economy, which removes the effect of growth.
Consumer price inflation is the change in the price index over the previous year.

Money

M0 (the monetary base) is cash plus banks' reserves at the Fed.
M1 is cash and checking deposits. Since May 2020 it also counts savings deposits, which is why its line steps up in 2020 without any change in how much money there was in total: M2 had always counted those deposits.
M2 is M1 plus small time deposits and retail money-market funds.
Velocity is GDP divided by M2: how many times a dollar of M2 is spent on the economy's output in a year. It falls when money is held rather than spent.
Federal debt per dollar of M2 divides the two stocks. It is a way to put the size of the debt next to the money in the system, not a measure of capacity to pay.

Money and bonds

A central bank pays for the bonds it buys with newly created reserves, which raises M0; when bonds it holds mature or are sold without being replaced, reserves are drained. That is how bond buying and the money supply connect.

Disclaimer

Slowio is an educational and analytical tool. Nothing on this page is investment advice, a recommendation or an offer to buy or sell any security. Figures come from public statistics and market data that may contain errors or delays; always verify against primary sources and do your own research before taking any decision.