Mid-Market Customer Success Manager in London

Some mid-market CSMs are at their best when the accounts are calm, the renewals are predictable, and the playbook tells them what to do next. The ones who will thrive in this role think differently. They look at a portfolio and already see what the data isn't telling them - the account about to shift, the expansion no one's asked for yet, the customer underutilising the platform in a way that will eventually cost them. They treat commercial ownership as the most interesting part of the job and understand the impact they have on the wider business. They have the desire to learn how AI is changing what excellent CS looks like and build it into the way they work.

At Semble, we're transforming private healthcare with our SaaS clinical system. Already trusted by thousands of clinicians and used in the care of more than 10 million patients, we're the UK market leader in private primary care and the fastest-growing practice management software provider. Following our recent £30m Series C funding round backed by Revaia, Partech, Mercia Ventures, and Octopus Ventures, we're scaling rapidly, and we need an exceptional Mid-Market Customer Success Manager to drive impact across our core customers.

Location: This is a London-based hybrid role. In the Success team, we expect two days per week in our London office, with flexibility for the remainder. Regular client visits are part of the role, and you should be comfortable with travel across the UK.

The role: Private healthcare in the UK is scaling fast. Semble sits at the centre: clinical records, scheduling, billing, patient communications, and the flexibility to connect with virtually everything else a practice depends on. For clinics, a platform they can genuinely rely on means their attention stays where it belongs, on the people in their care and that is what makes this work really matter.

As a Mid-market CSM you will own a portfolio of accounts, with values ranging between £16k-£60k+ ARR, with an average ACV of £20K ARR and growing as Semble scales post Series C. You cover the full customer lifecycle, from sales handover through to onboarding, continual adoption, expansion, and renewal. These are not simple accounts; they involve multi-site practices, complex migrations, API integrations, and multiple stakeholders with different definitions of success. Your job is to understand what each account is genuinely trying to achieve, operationally and commercially, and make sure Semble is central to how they get there.

This is not a role for someone who wants a settled playbook to follow. Post Series C, Semble is scaling quickly and the CS function is evolving with it. NRR is your core metric, and protecting and growing it means working closely across Sales, Product, Support, and Marketing. Your impact on those internal relationships matters as much as what you deliver directly with customers. The expectation is that you bring the discipline of excellent CS practice and the curiosity to challenge how it is done. Using AI to work smarter across a demanding portfolio, spotting patterns before they become problems, always looking for ways to focus more on what matters most - increasing time spent with customers.

You will report to Emma, our Head of CS, and join a team with a high standard and the ambition to keep raising it. Where the people in the role are expected to help shape how it evolves, not just execute within it.

What you'll own:

• Your portfolio's NRR: A clear, live view of every account: what needs protecting, what is at risk, and where the relationship needs active investment.
• The full customer lifecycle: From the moment a new account is handed over from Sales, you own everything that follows - discovery, onboarding, training delivery and continual adoption through to renewal.
• Value and growth across your portfolio: Knowing what your accounts are getting from Semble and where more value exists - for them and for us.
• Customer insight that lands: You will hear things across 55+ accounts that Product, Marketing, and leadership need to know.

What you'll bring:

• CSM experience with named account ownership: A track record of 3+ years managing a commercial SaaS portfolio across the full customer lifecycle.
• Commercial understanding and NRR ownership: You understand what your accounts are spending and what they should be getting for it.
• Experience running onboarding for complex accounts: Managing onboardings with genuine complexity.
• Comfort with a wide product: Experience with software that customers critically depend on to run their operations.
• A proactive, self-directed working style: You do not take account health at face value.
• AI literacy and genuine curiosity: AI is something you are actively engaging with.
• A clear upward trajectory in CS: Ideally including progression within the same organisation.
• Degree educated or equivalent.

Bonus points for:

• Experience working in healthtech or with customers in the private UK healthcare market.

Why join Semble?

• Be part of something big: be part of a mission-driven company transforming healthcare.
• Work with exceptional people: join a smart, ambitious, and supportive team.
• Impact: join an evolving Enterprise CS function with genuine scope to shape how we manage and grow our most strategic accounts.

What you’ll get in return:

• The great feeling that comes with knowing you do something that matters.
• Autonomy and ownership – we’ll set the vision and share the context, then we trust you to run with things.
• 36 days off: 25 holidays + bank holidays + 3 extra days (birthday and ‘feel good’ days).
• Private health Insurance – covering physical and mental health, as well as dental and optical!
• Get the tech you need - You will get the latest MacBook and take your pick across a wide range of equipment to set up your home office ergonomically.
• Work alongside an inspiring team – our two founders have started Semble after a successful startup exit.
• Fantastic office space in Central London, right outside Monument - with a roof terrace, weekly animations, loads of natural light, and cute doggies!
• The usual free bits coming with nice offices (barista coffee, tea, fruits, happy hours and activities...).

We welcome applications from people of all backgrounds and all walks of life, including any typically underrepresented groups in the technology industry. We also encourage applications from disabled and neurodiverse candidates, so if there are any adjustments we can make to support you throughout the recruitment process, please do let us know.

If you’re ready to take the next step in your career and make a real difference in healthcare, we want to hear from you.