UK Budget, 28th October 2026: An uneventful budget expected, but the reaction risks are skewed negative

• The government has positioned this to be an uneventful budget, and the reaction should follow, though risks are skewed to a negative response if Healey disappoints.
• Headroom likely to settle around GBP 15bln (prev. 23.6bln) after the hit from energy, yields and rate expectations, while manifesto pledges and a pro-business approach limit the levers.
• Bank surcharge likely the main revenue raiser; energy and defence spending the primary unknowns.
• DMO remit seen modestly higher, long-end share to be cut once again, which could partly offset a poorly-received speech.

• Potentially, set to be a relatively uneventful budget, as much of the unknowns have been clarified ahead of time, and as the Chancellor is set to meet the fiscal rules, which apply to 2029-30 for this event; rolls from April. The main outstanding points are: the final headroom level, somewhere around GBP 15bln; defence spending, expected to see “billions” announced, according to The Times; size of the bank tax, surcharge to at-most increase from 3% to 8%, raising GBP 2bln; Rosebank decision, following Jackdaw’s green light, is expected to be in 2026, weekend reports suggest the Chancellor is in favour; energy & cost of living, expectations on the cost of this vary extensively, and are (alongside defence spending) the main expenditure unknown, recent reports suggest a “green tax” in imported energy is under consideration. For taxation, the unknowns are the smaller levers the government can pull, such as the NIC base and whether pensioners are included or not, raising GBP 2-4bln, while CGT is not expected to be touched significantly, a smaller tweak or an exit/death-clause could raise a few billion each. Fresh sin-taxes are always a possibility, alongside measures to property, given the offsetting policy of Your First Home. Finally, PM Burnham has pledged to adjust the triple lock from 2030 to fund a NCS, though the adjustment falls outside the 2029-30 target year, and thus is largely moot.
• One of the big unknowns that the government can’t directly control is wages. The National Living Wage is provisionally expected to increase by 3.7%, but risks are very much skewed to the upside, lifting tax receipts and thus bolstering headroom, potentially with taxation thresholds frozen. Further, the average earnings growth view for 2027 should be revised higher from the Spring 2.4% view, potentially by as much as 60bps. However, it adds significantly to departmental pressures, though any change is likely to be deferred to the 2027 Spending Review, and is a factor of the triple-lock. Overall, wages present one of the most probable positive surprises for the headroom figure, as the benefit will be immediately present in the forecasts, while the departmental and other costs will be deferred or not counted. Upside that could offset much of the hit from higher yields to the Spring GBP 23.6bln headroom, and current assessments of around GBP 10-12bln.
• For the market, if everything is roughly as touted in the press and there are no major surprises to the above points, then the reaction should be relatively muted. Unless, the headroom does not increase from the current assumed GBP 10-12bln area, and if the tough choices are pushed back too far, a decision that has two detrimental impacts on UK assets: 1) a lack of fiscal credibility; 2) chimes with the 2027 Spending Review, but arguably the clearest signal yet that PM Burnham is thinking of an early election. Though, another cut to long-end issuance could be sufficient to offset some of the reaction to this, for the near term at least.
• Finally, the DMO remit is expected to increase for 2026-27. The Gross Financing Requirement (GFR) is seen increasing by GBP 8-15bln (prev. 268bln), with Gilt sales up by GBP 0-10bln, from the current GBP 246.2bln. Once again, the long-end share is likely to be reduced, though there is no firm consensus on the magnitude of any adjustment.

• Currently, as of the April revision, the Net Financing Requirement (NFR) for 2026-27 was forecast at GBP 251.2bln, (GFR at 268bln, for reference), featuring Gilt sales of GBP 246.2bln, with 9.1% from long, 30.9% medium and 38.6% short. The GFR was then projected to increase to GBP 307.6bln for 2027-28, before then dropping down in the following years to GBP 211bln by 2030-31.
• The remit is expected to increase for 2026-27. GFR and NFR are both seen higher by around GBP 8-15bln, with most views holding around the GBP 10bln mark. In terms of issuance, total Gilt sales are expected to increase by as much as GBP 10bln, but the consensus lies around the GBP 3.4bln figure.
• For the breakdown, long-end <7% (prev. 9%) and at the lowest share in over 35yrs, medium to tick up by around 4pp from 31%, short-end by around 3pp from 39%, while T-bills are to double in size from GBP 5bln to GBP 10bln. Another skew away from the long-end that is merited by yields in that bracket, 20yr+, continuing to lift and residing at multi-decade highs. Additionally, the shift is seen in DMO activity for the current FY, as there has only been one long-end sale despite over half of the year having passed, and while one has been announced for November and another three expected thereafter, this cadence could well be cut.
• If the long-end is cut as expected, this may be enough to shore up any fiscal slippage concerns from the Chancellor not taking action on the main spending concerns. As a reminder, much of the move on the last budget was driven by the DMO issuance skew away from the long-end.

• The forecast window is, usually, done over two weeks around five weeks before the budget announcement, equating to a 25th September cut off. Meaning the 10yr yield assumption is roughly where it is now, at about 5.36%; however, the 20yr and 30yr yield are now about 6-8bps higher. Note, this is not a fixed rule, but is an established convention. The final data inputs typically end the week before, so it should include the recent CPI (hot), Employment (hawkish) and PSNB, which FY YTD is 6bln above the OBRs view.
• For the headroom, the below forecasts and expected policies mean an eventual headroom of around GBP 15bln vs the previous forecast of GBP 23.6bln and a pre-budget assumed starting point of GBP 10-12bln, mainly due to higher yields, inflation and BoE Bank Rate expectations.

• The BoE is expected to begin its tightening cycle in November. Unless the budget is deemed as not fiscally credible, or similar, to an extent that a bond rout occurs, making it difficult and unwise for the BoE to tighten financial conditions further, given the potential growth implications of such a scenario. Nonetheless, the expected measures would theoretically give a small uplift to growth and a modest cut to inflation, but not to a degree to prevent a hike this year. However, it may add to the narrative that market pricing around the BoE by end-2027 is overdone, and could pare some of this, though a significant move is unlikely until after the November BoE.

Pre-trailed budgets of this kind, where the fiscal rules are met and the main measures have leaked in advance, have historically produced muted gilt reactions on the day; the damage in past UK fiscal events has come from surprises on credibility, not from the arithmetic itself. The operative distinction is between the headroom print and the issuance remit: thin headroom against the rules speaks to fiscal credibility and the long end's term premium, while the DMO's maturity skew is the mechanical lever, and prior episodes have shown a further cut to long-end supply can offset a poorly received speech in the near term by relieving duration absorption pressure at maturities already sitting at elevated yields. The asymmetry flagged here is the established pattern: an in-line outcome leaves little to trade, while a miss on headroom or a deferral of hard choices invites the familiar sequence of long-end underperformance, steeper curve and sterling softness, with the credibility question then feeding into how much room the central bank has to tighten into a bond rout. The known transmission channels are debt servicing sensitivity to yields across the curve, RPI linkage on index-linked stock, and the extent to which defence and energy spending is scored as capital versus current. What matters next is the final headroom figure against the pre-briefed range, the long-end share and bill skew in the remit, and whether anything arrives unbriefed, since unbriefed measures are what have historically repriced UK assets rather than the trailed ones.