Cambridge Article 4 HMO: What Investors Need to Know in 2026

If you’re weighing up an HMO investment in Cambridge, you’ve probably already come across the words “Article 4” somewhere in your research, usually attached to a warning. It’s worth pausing before you let that word decide anything. Cambridge does not have an Article 4 Direction in place today. Three things are happening instead: the council has agreed to build the evidence case for one, residents have petitioned for one, and the wider Local Plan is in its final consultation stage. None of that means Article 4 has actually arrived, and that gap matters for what you check before you buy. 

This guide sets out exactly where things stand, what already applies to a small HMO in Cambridge regardless of Article 4, and how to protect your investment while the position keeps moving. 

Where Cambridge’s Article 4 position actually stands 

Start with what hasn’t changed. A small HMO in Cambridge, three to six unrelated occupants sharing facilities, is still permitted development. You do not currently need planning permission purely because a property is changing from a family home to an HMO. That right only disappears once a council formally makes and confirms an Article 4 Direction for the relevant area, and Cambridge has not done that. 

What has changed is the political appetite. In June 2026, Cambridge City Council’s newly formed administration reached cross-party agreement to develop new controls on smaller HMOs and build the case for an Article 4 Direction. That’s a meaningful shift, but it’s a commitment to gather evidence, not a direction that’s already in effect. Back in February 2026, council officers had said the evidence available at that point wasn’t strong enough to support introducing one. The gap between “not enough evidence” in February and “let’s build the case” in June is exactly where a lot of investor confusion sits. 

This is where the HMO Architects Dual-Lens Approach™ earns its place. We’re not reading Cambridge’s planning position from the outside as commentators. We’re actively converting properties in the city right now, watching the same policy signals our clients are watching, and making live purchase and design decisions against them. That’s a different vantage point from a council FAQ page or a generic national guide to Article 4. 

A council that is building a case for Article 4 is not the same as a council that has one. Treat every headline accordingly, and always check the current boundary status directly with the council’s planning team before you commit to Cambridge HMO investment, not just a forum thread. 

What licensing and planning rules already apply today 

Regardless of where the Article 4 debate lands, two things already apply in Cambridge and won’t wait for a council decision. 

First, planning permission. HMOs with seven or more occupants already require planning and building control permission, Article 4 or not, because that size sits outside the permitted development route entirely. If your numbers only work with a larger HMO, you’re already in a full planning application, and should be pricing that timeline into your deal from day one, not treating it as a later formality. 

Second, licensing. Cambridge’s mandatory licence applies to any property occupied by five or more people forming two or more households. For the 2026/27 fee year, that licence costs £1,133, reduced to £1,000 if you apply at least eight weeks before an existing licence expires. It’s split into an application fee and a fee on grant, so budget for both stages rather than one lump sum. Licensing is entirely separate from Cambridge HMO planning permission: a licence doesn’t grant planning permission, and planning permission doesn’t grant a licence. Buying a property with an existing licence doesn’t transfer that licence to you either, you’ll need your own application, evidenced by your own records. 

That last point is where a lot of buyers get caught out at the compliance stage rather than the planning stage. If you’re taking on an existing HMO, it’s worth getting your licensing paperwork and tenancy evidence organised properly from day one; a tool like COHO exists specifically to keep licence records, inspection dates, and compliance paperwork in one place rather than scattered across email threads, which matters more in a city where the rules are actively shifting. 

The push for change: petition, council vote, and the Local Plan 

There are two separate tracks moving at once in Cambridge, and conflating them is the single most common mistake we see investors make when researching this market. 

The first is a resident-led petition, backed by the Guest Road Area Residents’ Association, which ran from May to July 2026. It called for two things: an Article 4 Direction covering small HMOs, and a 10% concentration threshold within a 100-metre radius, meaning any street already at that density would likely see new HMO planning applications refused. The council debated the petition in July, and it fed directly into the cross-party commitment from June to build the Article 4 case. 

The second, running on its own separate timeline, is the Greater Cambridge Local Plan. Its draft HMO policy already treats two or more adjacent HMOs as Cambridge HMO overconcentration, ahead of any Article 4 Direction, and flags that the councils are considering an Article 4 for particular locations rather than city-wide. This Cambridge Local Plan HMO policy is currently open for its final consultation until 25 September 2026, with adoption not expected until around September 2027. 

That’s the detail a generic guide to Article 4 won’t give you: Cambridge investors aren’t waiting on one decision, they’re watching two policy routes that could each land on a different timeline, cover different geographies, and interact with a specific street in different ways. This is exactly the kind of situation the Planning Evidence Test™ was built for, before you rely on any headline about Cambridge and Article 4, ask what evidence the council is actually acting on for your specific street, not the city as a whole. 

cOur own project mix in Cambridge reflects how varied that street-level picture already is. On Gunhild Close, we converted a family home into a six-bed HMO, navigating a planning application that had to be withdrawn and resubmitted once volume concerns surfaced from undocumented earlier extensions. On Hobart Road, we designed a seven-unit Sui Generis HMO for professionals and students, working through a council condition on communal space that reshaped the layout mid-project. Both show the same thing: getting a Cambridge HMO through planning is rarely about the headline rule, it’s about how that rule meets a specific site.

Gunhild Close bedroom

What this means for your next Cambridge purchase 

None of this means you should pause a genuinely good Cambridge deal. It means the due diligence has to go one level deeper than it would in a city with a settled position. 

Before you exchange, check the existing HMO concentration on and immediately around the street, not just whether the property itself is currently an HMO. Confirm which occupant threshold your numbers actually depend on, because 3–6 occupants and 7+ occupants sit on entirely different planning routes and timelines. And if you’re buying an existing HMO rather than converting one, ask for licensing and lawful-use evidence directly, not a verbal assurance from the seller, since licences don’t transfer and can’t be taken on trust. 

Should You Buy This Cambridge Property as an HMO Right Now? 
If you answer “no” to any of these, get advice before you exchange: 

• Have you checked the street for existing HMO concentration, not just the property itself? 

• Do you know whether your numbers depend on 3–6 or 7+ occupants, and which planning route that implies? 

• If buying an existing HMO, have you seen documented evidence of licensing and lawful use? 

In Cambridge right now, the numbers question and the planning question are the same question. Treat them separately and you’ll price the deal wrong in one direction or the other. 

If you are investing in Cambridge and you are still worried about planning or compliance? Book a strategy session today and we’ll walk through your specific site against the current position, not a generic national guide. 

If you’d rather keep watching how Cambridge’s Article 4 position develops before you commit, our HMO Masters newsletter covers exactly this kind of live planning shift as it happens. 

FAQs

Is there an Article 4 Direction in Cambridge yet? 

No. As of today, no Article 4 Direction covering HMOs is in force in Cambridge. The council has committed to building the case for one following a June 2026 cross-party agreement, and a resident petition pushed for it over the summer, but neither has resulted in a confirmed direction. 

Can I still convert a house into a small HMO in Cambridge without planning permission? 

Yes, for now. Converting a standard home into a small HMO of 3–6 unrelated occupants remains permitted development in Cambridge. That would change only if and when a formal Article 4 Direction is made and confirmed for the relevant area. 

What might change in Article 4? 

Two things to watch: whether the council moves from “building the case” to actually making an Article 4 Direction, and how the Greater Cambridge Local Plan’s overconcentration policy lands once its current consultation closes on 25 September 2026. Either could shift the picture for a specific Cambridge street before the other does. 

Do I need a licence for a small HMO in Cambridge? 

Yes. Cambridge requires a mandatory HMO licence for any property occupied by five or more people forming two or more households, regardless of whether Article 4 applies. This is a separate requirement from planning permission, so a small HMO can be fully compliant on planning grounds and still need a licence. 

How much does an HMO licence cost in Cambridge in 2026? 

For the 2026/27 fee year, Cambridge’s mandatory HMO licence costs £1,133, reduced to £1,000 if you apply at least eight weeks before your current licence expires. The fee is split into two parts: £736 on application and £397 on grant of the licence. 

What counts as HMO overconcentration in Cambridge? 

Under the draft Greater Cambridge Local Plan, two or more adjacent HMOs are treated as overconcentration, a threshold that applies ahead of any Article 4 Direction and could affect new HMO planning applications on that basis alone. A separate resident petition also proposed a 10% concentration threshold within a 100-metre radius, though this has not been adopted as council policy.