UK Gilt Crisis 2022: The LDI Doom Loop

Key Takeaways

• A September 23 mini-budget of roughly GBP 45 billion in unfunded tax cuts cracked the gilt market.
• Thirty-year gilt yields jumped about 130 basis points in days, three times any prior move.
• Leveraged LDI pension hedges faced about GBP 66 billion in collateral calls, forcing fire sales.
• The Bank of England backstopped the market and Prime Minister Liz Truss resigned within weeks.

Background

By 2022, UK defined-benefit pension schemes had spent two decades reshaping how they invested. These schemes promise fixed, often inflation-linked payments to retirees stretching out 30 years or more. The present value of those promises swells when long-term interest rates fall, so falling yields had repeatedly widened pension deficits through the low-rate years after 2008.

The fix was liability-driven investment, or LDI. An LDI strategy holds long-dated gilts and interest-rate derivatives so the assets gain value when rates fall, offsetting the matching rise in the pension liability. To hedge a very long liability without tying up all their cash, schemes ran the hedge with leverage, using repo borrowing and interest-rate swaps. That freed up the rest of the portfolio for return-seeking assets like equities and credit.

The scale was large. By the end of 2021 there was an estimated GBP 1.4 trillion of assets held in LDI strategies in the UK, and LDI accounted for about 80 percent of the country's defined-benefit market, far more than the roughly 40 percent in the US or 35 percent in the European Union. Around 85 percent of UK LDI assets sat in segregated mandates run for a single scheme, with the rest in multi-investor pooled funds.

Leverage was the hidden catch. A leveraged hedge has to post collateral when its bonds lose value. LDI funds typically held a buffer sized to absorb a move of roughly 100 basis points in yields, a level that historical experience suggested was more than enough. That assumption was about to be tested by a move three times larger.

What Happened

The trigger was political. On September 23, 2022, Chancellor Kwasi Kwarteng, serving the new Prime Minister Liz Truss, delivered a fiscal statement titled "The Growth Plan." It set out around GBP 45 billion of tax cuts by 2026/27, including a cut to the basic rate of income tax, the abolition of the 45 percent additional rate, a reversal of a National Insurance rise, the cancellation of a planned corporation-tax increase, and a stamp-duty cut. It was the biggest package of tax reductions since 1972, was largely unfunded by spending cuts, and arrived with no independent Office for Budget Responsibility forecast.

Markets read it as a loss of fiscal discipline and sold. The day before, a routine Bank of England rate decision had moved 30-year gilt yields by only about 20 basis points, in line with other countries. The Growth Plan caused a clean break.

• Friday, September 23: The Growth Plan is announced; gilt yields spike and sterling falls sharply.
• Monday, September 26: The pound hits an all-time low of about 1.0327 against the US dollar, below its 1985 low and the weakest since decimalisation in 1971.
• September 23 to 28: Thirty-year nominal gilt yields rise about 130 basis points, and 30-year inflation-linked yields about 170 basis points, cutting the price of those bonds by roughly 24 and 38 percent.
• Tuesday/Wednesday, September 27 to 28: LDI funds face mass collateral calls; many pooled funds approach negative net asset value and the gilt market stops functioning.
• Wednesday, September 28: The Bank of England announces emergency, temporary purchases of long-dated gilts to restore order.
• October 11: The Bank adds inflation-linked gilts to its purchases; Governor Andrew Bailey tells funds they have three days to fix their positions.
• October 14: The intervention ends as scheduled; the same day Kwarteng is dismissed.
• October 20: Truss resigns after 44 days in office.

The move was extraordinary by any historical yardstick. The roughly 130 basis point jump in long-maturity nominal gilt yields was about three times the size of any comparable move on record, blowing straight through the 100 basis point buffer most LDI funds carried.

Why It Happened

The crisis was not a credit event. UK gilts carry no real default risk, and the government did not miss a payment. It was a liquidity event driven by leverage, collateral mechanics, and concentration, set off by a fiscal shock.

Start with the collateral spiral. When gilt prices fell, the leveraged LDI hedges lost mark-to-market value, and their repo and swap counterparties demanded more collateral, in cash, often the same day. Between the September 23 announcement and the September 28 intervention, those collateral and variation-margin calls were estimated at about GBP 66 billion. To raise that cash, funds had to sell assets, and the most saleable assets were the gilts themselves.

That selling fed the fire. Each round of forced gilt sales pushed prices lower and yields higher, which produced fresh losses and fresh collateral calls, which forced more selling. The Bank of England described the danger as "self-reinforcing 'fire sale' dynamics." This is the "doom loop": a hedge designed to reduce risk became, under leverage and stress, an engine of forced selling.

Concentration made it worse. Pension and LDI funds are the largest holders of long-dated and index-linked gilts, so when they all needed to sell at once there was no natural buyer to absorb the flow. Market intelligence early in the week suggested at least GBP 50 billion of additional long-dated gilt sales were needed quickly, against recent average trading volumes of only about GBP 12 billion a day. Liquidity simply was not there; in the first days of stress, fewer than GBP 5 billion of sales actually completed even as yields rocketed.

The shock then spread. Because gilts sit at the core of UK finance, the dislocation pushed up interest-rate swaps used to price mortgages, with the two-year swap reaching around 6 percent. Roughly 40 percent of mortgage products were pulled as lenders could no longer price them. What began as a pension-hedging problem was turning into a credit-supply problem for households and businesses.

The deepest cause was a risk-management gap. A 100 basis point stress buffer looked prudent against decades of data, but it assumed the world would keep behaving as it had. It did not account for a move three times larger arriving in days, nor for the operational reality that many pooled funds could not move cash fast enough to meet calls in time.

By the Numbers

• Mini-budget size: about GBP 45 billion of tax cuts by 2026/27, the largest since 1972. (House of Commons Library)
• Sterling low: an all-time low of roughly 1.0327 against the US dollar on September 26, 2022. (Washington Post)
• Yield spike: 30-year nominal gilt yields rose about 130 basis points, and inflation-linked about 170 basis points, by September 28, roughly three times any comparable historical move. (Wilkins, GCEPS WP 336)
• Price drop: approximately 24 percent on 30-year nominal gilts and 38 percent on 30-year real gilts. (Wilkins, GCEPS WP 336)
• LDI scale: an estimated GBP 1.4 trillion in UK LDI strategies at end-2021, about 80 percent of the UK defined-benefit market. (Wilkins, GCEPS WP 336)
• Collateral calls: about GBP 66 billion between September 23 and 28. (Wilkins, GCEPS WP 336)
• Liquidity gap: at least GBP 50 billion of needed sales versus roughly GBP 12 billion average daily volume. (Wilkins, GCEPS WP 336)
• Backstop size: purchases of long-dated conventional gilts (residual maturity over 20 years) initially up to GBP 5 billion per auction, implying a maximum of about GBP 65 billion over 13 trading days. (Bank of England; Bank of England Quarterly Bulletin)
• Actual purchases: about GBP 19.3 billion bought, roughly two-thirds conventional gilts and the rest index-linked. (Wilkins, GCEPS WP 336)
• Time in office: Liz Truss resigned after 44 days, the shortest-serving UK prime minister, beating George Canning's 119 days. (TIME)

Aftermath

The Bank of England's intervention was deliberately narrow. On September 28, acting on a Financial Policy Committee recommendation, it announced temporary, targeted purchases of long-dated gilts, warning that if "dysfunction in this market" continued "there would be a material risk to UK financial stability" and "an unwarranted tightening of financing conditions and a reduction of the flow of credit to the real economy." It stood ready to buy conventional gilts with a residual maturity of more than 20 years, initially up to GBP 5 billion per auction, with auctions running from September 28 until October 14. On October 11 it added inflation-linked gilts, which were central to pension and LDI repo positions.

Crucially, the Bank priced the operation as a backstop, not stimulus. It bought only at relatively distressed prices, so take-up stayed limited to funds that genuinely needed it. In the end it bought about GBP 19.3 billion of gilts, well below the roughly GBP 65 billion ceiling. The Bank made clear the support was time-limited; Governor Andrew Bailey told funds at an event on October 11, "You've got three days left now. You've got to get this done." The facility closed on October 14 as scheduled, and the Bank unwound the holdings between November 29, 2022 and January 12, 2023 without reigniting the stress.

The political cost was steep and fast. Kwarteng was dismissed on October 14 and replaced by Jeremy Hunt, who reversed almost all of the tax cuts. Truss resigned on October 20, after 44 days, becoming the shortest-serving prime minister in UK history. No criminal wrongdoing was alleged against anyone in this episode; this was a policy and risk-management failure, not a fraud.

Regulators then moved to harden the system. Pension and LDI funds rebuilt resilience during and after the crisis, lowering leverage by selling about GBP 37 billion of gilts and raising an estimated GBP 33 billion from their pension-scheme clients. The Pensions Regulator and the Financial Conduct Authority issued guidance pushing leveraged LDI arrangements to hold a far larger stress buffer, on the order of 250 basis points plus an operational buffer, so a future yield spike would not force the same scramble. The Bank of England also launched a system-wide exploratory scenario to map the hidden links between banks and non-bank funds that the crisis exposed.

Lessons for Investors

1. Leverage turns a hedge into a liability. The LDI strategy was sound in concept: match the pension liability so falling rates could not blow a hole in funding. Leverage made it fragile, because a leveraged hedge must post cash collateral exactly when its assets are falling. When you own anything financed with borrowing or derivatives, the real question is not "is this a good position" but "can I fund the margin calls in a stress."

2. A government bond is risk-free of default, not of price. Gilts never threatened to default, yet 30-year prices fell roughly a quarter in days. "Safe" assets still carry interest-rate and liquidity risk, and a long-duration safe asset can move violently. Treat duration as a real exposure, not a footnote.

3. Stress tests fail when the scenario has no precedent. Funds buffered for a 100 basis point move because nothing bigger had happened. The actual move was about three times larger. History sets a floor on how bad things can get, never a ceiling. Size your buffers for the move you cannot yet imagine, not the worst one in the dataset.

4. Concentration removes your exit. Pension and LDI funds were the natural buyers of long-dated gilts, so when they all sold together there was no one on the other side. Crowded positions look liquid until everyone reaches for the door at once. Before you count on selling in a crisis, ask who will be buying.

5. Speed is its own risk factor. The doom loop ran its course in days, and collateral had to be found in hours. A plan that needs a week to raise cash is no plan if the market gives you an afternoon. Build liquidity and operational readiness for stress that moves faster than you expect.

Frequently Asked Questions

What was the UK gilt crisis 2022 in simple terms? The UK gilt crisis 2022 was a sudden crash in UK government bond prices after a September 23 mini-budget of unfunded tax cuts. The crash threatened pension funds and forced the Bank of England to step in with emergency bond buying.

Why did the gilt crisis happen? A large package of unfunded tax cuts made investors doubt UK fiscal discipline, so they dumped gilts and yields spiked far faster than expected. Pension funds running leveraged LDI hedges then faced huge collateral calls and had to sell more gilts to raise cash, which pushed prices down further in a self-reinforcing loop.

How much money was involved in the gilt crisis? LDI funds faced an estimated GBP 66 billion of collateral and margin calls in five days, against a UK LDI sector of about GBP 1.4 trillion at end-2021. The Bank of England set up a backstop of up to about GBP 65 billion but ultimately bought only around GBP 19.3 billion of gilts.

Could the gilt crisis happen again today? Regulators forced LDI funds to hold much larger stress buffers, roughly 250 basis points plus an operational buffer, so a similar yield spike would be less likely to force fire sales. Yet leverage, concentrated pension holdings, and the speed of modern markets all remain, so the underlying pattern has not vanished.

What is the main lesson from the gilt crisis? A strategy built to reduce risk can become the source of risk once leverage and collateral calls are added. Funding and liquidity in a stress matter more than whether a position looks safe in calm markets.

Sources

1. Bank of England. Bank of England announces gilt market operation. September 28, 2022. https://www.bankofengland.co.uk/news/2022/september/bank-of-england-announces-gilt-market-operation
2. Bank of England. Financial stability buy/sell tools: a gilt market case study. Quarterly Bulletin, 2023. https://www.bankofengland.co.uk/quarterly-bulletin/2023/2023/financial-stability-buy-sell-tools-a-gilt-market-case-study
3. Wilkins, C. A. Financial Stability and Monetary Policy: Lessons from the UK's LDI Crisis. Griswold Center for Economic Policy Studies, Princeton University, Working Paper No. 336, August 2024. https://gceps.princeton.edu/wp-content/uploads/2024/08/wp336_Carolyn-Wilkins_UK-LDI-Crisis.pdf
4. House of Commons Library. The September 2022 fiscal statement: a summary (CBP-9624). https://commonslibrary.parliament.uk/research-briefings/cbp-9624/
5. The Pensions Regulator. Maintaining liability-driven investment (LDI) resilience guidance. https://www.thepensionsregulator.gov.uk/en/media-hub/press-releases/2023-press-releases/new-ldi-guidance-published-by-tpr--to-ensure-schemes-minimise-risk
6. CNBC. Bank of England's Bailey tells pension funds they have 3 days to rebalance. October 11, 2022. https://www.cnbc.com/2022/10/11/bank-of-englands-bailey-tells-pension-funds-they-have-3-days-to-rebalance.html
7. The Washington Post. British pound falls to all-time low against dollar after taxes slashed. September 26, 2022. https://www.washingtonpost.com/world/2022/09/26/uk-gbp-pound-falls-usd-dollar/
8. TIME. Liz Truss Is Now the Shortest-Serving Leader in U.K. History. October 20, 2022. https://time.com/6223441/shortest-serving-uk-prime-minister-liz-truss/

Disclaimer

This article is educational content only and is not financial advice. Nothing here is a recommendation to buy, sell, or hold any security. Consult a licensed advisor before making investment decisions.