Enterprise Customer Success Manager

Proton.ai; Cambridge; Hybrid; GBP 67,000 - 105,000; Full time

Benefits offered by this job

Stock options

Flexible schedule

Unlimited PTO

Wellness days

Parental leave

Health benefits

401k match

Company off-sites

Job summary

Proton.ai is seeking an Enterprise Customer Success Manager to own a ~$2.5M ARR book of enterprise and mid-market customers. You’ll advise executives, craft AI strategies, and partner with Sales, Product, and Engineering to drive adoption and renewals.

This hybrid role is based in the greater Boston area with 10+ customer visits per year. You’ll build trust at all levels, identify expansion opportunities, and translate insights into actions that fuel customer growth and long-term partnerships.

Qualifications

• 3–4+ years in Customer Success or a similar customer-facing role in B2B SaaS.
• Early-stage CS experience is a plus.
• Able to adapt quickly and move the needle for customers.
• Comfortable speaking with executives and building strategic relationships.

Responsibilities

• Own a ~$2.5M ARR book of enterprise and mid-market customers.
• Lead business conversations about revenue, productivity, and goals.
• Collaborate with Product, Engineering, and Sales to drive adoption and renewals.
• Identify opportunities to expand and partner with Sales to close them.
• Turn insights and usage data into actionable recommendations for executives.
• Represent customer needs to Product and CS teams to improve solutions.

Skills

Customer success

B2B SaaS

Executive communication

Problem solving

Tools

CRM tools

Data analytics tools

AI agents

Job description

• As an Enterprise Customer Success Manager, you’ll own a ~$2.5M ARR book of enterprise and mid‑market customers. One day you might be in a CEO’s office helping them craft their AI strategy. The next, you might be riding along with a rep to see why a workflow isn’t sticking. The work will stretch you. It’s also deeply rewarding, because you’ll see your impact show up in your customers’ growth
• This is a hybrid role based in the greater Boston area, with 10+ customer visits a year
• Reporting to the Manager of Customer Success
• Get curious about the business. Dig into how each customer sells, what’s slowing them down, and what growth looks like for them. Ask why, then ask why again
• Lead business conversations. Talk with customers about revenue, rep productivity, and their goals. Show how Proton helps them get there
• Own the outcome. Treat your customers’ success as your own. If we don’t have an answer yet, pull in Product, Engineering, Implementation, or Sales and keep moving until we do
• Build relationships at every level. Earn trust with reps, managers, and executives so everyone sees the value Proton delivers
• Turn insight into action. Use data and usage trends to spot what’s working and what isn’t. Bring a clear recommendation to every Executive Business Review
• Grow the partnership. Spot opportunities to expand, and partner with Sales to bring them to life
• Use AI as a resource to solve problems. Leverage internal AI tools to build your own skills, agents to find answers faster, uncover insights, automate work, and build solutions that save customers time and help them grow
• Call risk early. Be honest when an account is off track, and come with a plan to fix it
• A rising tide lifts all boats. Bring customer insights back to Product and the CS team so we keep getting better together
• Own adoption + renewal success. You will be responsible for maintaining active and engaged customers, and supporting high adoption from implementation through renewal cycles

Benefits

• Company stock options: We believe everyone should own a part of something they help build, so we offer company equity to all employees.
• Flexible schedule: Work is important to us. As is being flexible. We know life doesn’t always land outside of a 9-5 schedule and make space for you to live your life.
• Unlimited Required PTO: We offer unlimited PTO, and we make sure everyone takes at least 2 weeks off per year.
• Company wellness days: In addition to company holidays, we offer wellness days, when the whole company takes a day off to rest and recuperate.
• 12 weeks paid parental leave: 12 weeks paid parental benefit for all parents (birthing, non-birthing, adopting, fostering).
• Health benefits: Get access to great healthcare benefits.
• 401k with employer contribution: We believe it’s important to help our team plan for the future. For U.S. employees (for now), we directly contribute a 3% match of your salary to a 401k.
• Company-paid off-sites: Enjoy in-person brainstorming and team-building. All expenses covered so you can focus on bonding with the entire team.

Have 3–4+ years in Customer Success or a similar customer-facing role in B2B SaaS. Early-stage experience is a plus. You like that no two days look the same, can adapt, and stay focused on moving the needle for customersCelebrate wins as a team and share learningsLove learning how businesses work, and can’t help asking “why.”Feel energized by ambiguity and enjoy switching between big-picture strategy and hands‑on problem-solvingAre technically curious. You’re not an engineer, but you enjoy learning CRMs, data tools, and AI agents and helping customers get the most from themAre consultative, creative, and solution-oriented in nature. When you don’t have the answer, you know who to call and you bring a planCan speak confidently with executives, and know what makes them tickTake extreme ownership. You follow through, follow up, and don’t let a customer’s problem sit stillKnow what it takes to help a team adopt a new tool and stick with it