Hampshire and Solent Combined County Authority Explained

If you live, work or study in Hampshire, the Isle of Wight, Portsmouth or Southampton, there is a new layer of decision-making to know about. According to the statutory instrument published on legislation.gov.uk, the Hampshire and the Solent Combined County Authority was created on 3 June 2026, with most of the rules taking effect on 4 June 2026. In plain English, this is a new legal body that lets the four councils act together on some issues that cut across council boundaries. It does not abolish the existing councils. Hampshire County Council, Isle of Wight Council, Portsmouth City Council and Southampton City Council all remain in place.

A combined county authority is best understood as a shared regional authority. The regulations make it a body corporate, which means it can hold powers, make decisions, receive funding and carry out functions in its own name. It covers the combined area of the four constituent councils and can use powers given directly by these regulations, by other laws, or through delegation. **What this means in plain English:** ministers want some big regional questions to be handled jointly rather than four times over. That is most obvious in transport, but the regulations also open the door to work on regeneration, information sharing and other strategic issues.

One of the most important dates is still ahead. The regulations create a mayor for the area, but the first mayoral election is set for 4 May 2028, and the first term begins on 8 May 2028. After that, elections will take place every four years on the ordinary local election day. Until then, the authority works without a mayor. It must choose a chair and vice-chair from among its members, and those posts disappear at the end of the day before the first mayor takes office. The future mayor will also be allowed to appoint one political adviser, employed by the authority for that mayor’s term, and the post is treated as politically restricted.

The make-up of the authority shows how representation is being balanced. Each constituent council appoints one elected member, but Hampshire County Council appoints one extra elected member, so there are five constituent members in total before the mayor arrives. Each council must also appoint substitute members, and the authority can include up to five non-constituent or associate members. Before 8 May 2028, some decisions need all five constituent members to agree, including the budget, the local transport plan and the constitution. Most other decisions are by simple majority, but once the mayor arrives that majority must include the mayor, or a deputy mayor acting in the mayor’s place. There is also a local safeguard: if a decision would place a financial liability on a council, affect land in its area, or use powers in its area, the member from that council must approve it. Even the meeting rules change over time: before the mayor, the chair or vice-chair plus three constituent members must be present; afterwards, the mayor or deputy mayor plus four constituent members are required.

Transport is where the new authority gets some of its clearest powers. From the start, it can exercise certain public transport functions alongside the four councils, but only if every council affected agrees. That means the authority can act regionally, but local councils keep a strong say over what happens in their own patch. Local transport planning changes in two stages. From 4 June 2026 until 8 May 2028, the combined county authority can work on local transport plans at the same time as the constituent councils. From 8 May 2028, those planning powers move away from the councils and sit with the combined county authority instead, and the regulations then make them functions exercisable only by the mayor.

The regulations also give the authority a grant-making power that normally belongs to a minister under section 31 of the Local Government Act 2003. The combined county authority can use that power in relation to the area at the same time as a minister can. If it decides how much grant should go to a constituent council for highway work, it must consider whether the council will still have enough money to do the job properly and what other funding is already available. **Why that matters:** money rules can be dry on paper, but they decide who can fund road maintenance, transport upgrades and longer-term schemes. Once the mayoral system begins on 8 May 2028, this grant power also becomes a mayor-only function, even though members and officers of the authority can help with the work.

The new authority will be funded by the constituent councils. The regulations say the councils must meet the costs that are reasonably attributable to the authority’s functions, including certain mayoral costs if those are not covered from other resources. If the councils cannot agree how to split the bill, the fallback rule is population share, using official resident population estimates. Beyond transport, the authority is also given concurrent powers linked to information sharing under the Crime and Disorder Act 1998 and to economic development and regeneration under the Localism Act 2011. So while transport is the headline, the legal design is wider than buses and roads.

A good deal of the statutory instrument is administrative plumbing, but it still tells us how the new body will work day to day. It adjusts the first accounting period, sets rules on meetings, minutes and standing orders, and allows allowances for roles such as the mayor, deputy mayor, scrutiny committee members and audit committee members if an independent remuneration panel recommends them. The authority is also treated like a local authority for publishing information and for bringing or defending legal proceedings. That might sound minor, but this is the part that turns a political agreement into a functioning institution. It is how a new authority moves from being an announcement to being something that can meet, vote, publish, pay and be held to account.

In the explanatory note, the Government says no full regulatory impact assessment was prepared because the instrument is not expected to raise costs for the business or voluntary sectors. It also says the effect on the public sector should be greater operational efficiency, which could reduce costs over time. For local readers, the simplest takeaway is this: Hampshire, the Isle of Wight, Portsmouth and Southampton now have a formal regional authority with legal powers of its own. For the next two years it works in a tightly shared model with the councils. From 8 May 2028, it becomes more clearly mayor-led, especially on transport. If you want to know when this starts to feel real at the ballot box, circle 4 May 2028.