Andy Burnham’s surge toward the premiership has investors scrutinising fiscal playbook his team may rewrite. After a mis‑step last year that rattled gilt markets, MP‑elect pledged to follow Chancellor Rachel Reeves’ rules that require spending to be covered by tax receipts and debt to fall as a share of GDP. He also vowed no carve‑out for defence spending and aims to keep inflation in check.

Burnham surrounds himself with economists who have long argued the current fiscal rules are too short‑term and choke investment. Advisers include former BoE chief economist Andy Haldane, ex‑Goldman Sachs chief Jim O’Neill and former OBR chair Richard Hughes – all urging looser rules. O’Neill has labeled the limits “petty and arbitrary,” while Haldane calls reform “overwhelming.”

Reeves’ October 2024 budget already stretched the framework, redefining the debt measure to free up as much as £70 billion of borrowing over five years. Any further tweak will hinge on who Burnham appoints as chancellor and how he handles the looming Thames Water nationalisation debate. Markets will price the move, but short‑term gilt volatility is likely to stay significantly muted.