Getting to Know You: Senior Accountant, Mario Cotto

At Insource, every engagement is a chance to help mission-driven organizations thrive. In this edition of our recruitment series, meet Mario Cotto, a Senior Accountant who supports clients end-to-end – from bookkeeping and payroll to month-end close and financial reporting.

From entry-level to impact

Mario joined Insource fresh out of college after spotting an entry-level Staff Accountant role. The draw? Variety. “I’d always imagined accounting for one entity – Insource meant learning across multiple clients with different needs and timelines,” he says. Four years on, he’s grown into a Senior Accountant, applying classroom theory to diverse real-world scenarios every day.

A hiring process that feels personal

What set Insource apart during interviews was how thoughtful and human the process felt. Mario met team leads and even interviewed with senior leadership – a level of access he didn’t experience elsewhere. “It made the process feel considered, like the company genuinely cared about the right fit for the team as well as the role.”

Early goals – and a steep, rewarding learning curve

Starting out, Mario’s goal was straightforward: gain experience fast. Consulting delivered exactly that. Supporting multiple nonprofits with different boards, deadlines, and systems accelerated his learning and sharpened his judgment – far beyond what a single-entity role could offer.

Biggest challenge: letting go of “perfect”

Like many early-career professionals, Mario initially worried about mistakes. The shift came with coaching and trust: ask for help, learn quickly, move forward. “I had to stop fixating on getting everything perfect the first time and lean into the support around me.”

Day to day: time-bound, client-driven, never the same

There’s no “typical” day. Cycles drive the calendar – month-end close in week one, reporting in week two, weekly payrolls, and seasonal peaks like audit prep. Layer in ad-hoc client requests, and every day demands focus, flexibility, and clear communication.

Growth you can see

Mario’s path from Staff Accountant to Senior Accountant reflects the upward mobility built into Insource’s model. Constant exposure to new tools, scenarios, and stakeholders means continuous professional development – on real work that matters.

Support that shows up

Regular bi-weekly check-ins with his manager help right-size workload, unblock challenges, and celebrate wins. “My manager’s a great friend – someone I’d grab a coffee with outside work. That level of trust makes the work better.”

Proud moments: powering nonprofit missions

What motivates Mario most is seeing clients continue their mission year after year. “Meeting executive directors and CFOs who are genuinely focused on community impact – it’s inspiring. Helping them stay financially strong so they can keep serving is incredibly fulfilling.”

Life outside the ledger

Balance is non-negotiable. After work, Mario is likely at Muay Thai four times a week, reading, or catching a film – habits a healthy work-life rhythm makes possible.

“Is Insource the right fit?”

“100%.” Four years in, Mario describes Insource as home: kind people, candid communication, and a culture where it’s always “us and the problem,” not “us versus each other.”

Considering your next move? If you’re energized by variety, growth, and purpose-driven work, Insource could be the place you’ll grow – and belong. Reach out to us at insource@insourceservices.com or 781-235-1490 to learn more today.