Mark Leinson
Seekonk,USA
Summary
Dynamic sales professional with established success at T-Mobile, specializing in strategic account management and cultivating client partnerships.
Overview
32
32
years of professional experience
3
3
Certifications
Work History
Mid Market Account Executive
T-Mobile
Norton, USA
08.2025 - Current
- Drove growth across a mid-market territory with a hunter mindset, expanding pipeline and securing 95%+ retention through proactive, data-driven account planning.
- Led consultative discussions on network security, device security, and data-protection best practices, improving customer security posture across mobility, IoT, and remote-work environments.
- Sold and supported cybersecurity offerings including secure network access, threat detection, private APN, mobile-device security, and encrypted communication solutions.
- Delivered secure M2M/IoT deployments, advising on SIM-level security, device authentication, encrypted data transmission, and secure asset-tracking architectures.
- Conducted security-focused assessments with IT and operations leaders to identify vulnerabilities, compliance needs, and risk-reduction opportunities.
- Drove 25-40% efficiency gains by guiding secure deployments of mobility, IoT, and workflow-automation solutions.
- Achieved 105% Q1 quota by building pipeline quickly and aligning secure connectivity solutions with customer risk profiles and operational priorities.
- Built strategic account plans using usage and security data to identify gaps, expand adoption, and increase ROI.
- Generated double-digit revenue growth through consultative selling, cross-selling, and upselling secure mobility, IoT, and network-protection solutions.
- Maintained 98%+ forecasting accuracy with strong CRM discipline and data-driven territory execution.
Enterprise Account Manager
Comcast
Plymouth, USA
02.2024 - 07.2025
- Advised mid-market and enterprise customers on DDoS, SASE, managed firewalls, and threat-monitoring solutions.
- Performed security assessments to identify vulnerabilities and align solutions to customer risk and compliance needs.
- Designed secure network architectures with IT and security teams using fiber, Ethernet, SD-WAN, and managed security services.
- Led technical discussions on firewalls, intrusion prevention, endpoint protection, and secure cloud access, translating complexity into business value.
- Delivered tailored demos, proof-of-concepts, and security reviews with cybersecurity engineers.
- Increased revenue through cross-selling cybersecurity add-ons, boosting account stickiness and reducing churn.
- Achieved 100% quota attainment while delivering high ROI through improved security posture, reduced risk exposure, and optimized network performance.
- Maintained strong pipeline discipline and accurate forecasting across a high-volume territory.
Enterprise Account Manager
T-Mobile
Norton, USA
08.2022 - 09.2023
- Managed 150+ mid-market and enterprise accounts across diverse industries, advising on mobility, cloud productivity, and technology modernization solutions.
- Led consultative sales engagements to uncover workflow gaps and compliance needs, recommending tailored solutions including Microsoft O365, secure mobility, and collaboration tools.
- Drove full lifecycle adoption of O365 and cloud services, coordinating onboarding, training, and technical support to ensure smooth implementation.
- Built strong customer relationships and achieved 95%+ retention through proactive engagement and strategic account planning.
- Delivered business reviews with usage insights and optimization recommendations that improved communication and reduced operational friction.
- Partnered cross-functionally to resolve complex issues and maintain service continuity for mission-critical operations.
- Increased account value through targeted upsell and cross-sell of O365, secure mobility, cloud VOIP, IoT, and workflow solutions.
- Ranked #12 nationally at 257% to net revenue goal, demonstrating strong execution in customer success and consultative selling.
- Maintained 98%+ forecasting accuracy through disciplined CRM and structured follow-up.
Government Account Executive
T-Mobile
Norton, USA
04.2021 - 08.2022
- Drove public-sector new business acquisition, securing 17 new logos in one year through targeted outreach and strategic solution positioning.
- Executed with a strong hunter mindset, surpassing revenue targets while managing a full-cycle pipeline and navigating complex procurement processes.
- Sourced and developed high-value prospects via cold calling, networking, events, and lead-gen tools, consistently exceeding pipeline and growth goals.
- Expanded government account footprint by uncovering new opportunities and building long-term relationships with key stakeholders.
- Partnered cross-functionally to develop go-to-market strategies that strengthened public-sector presence and accelerated territory growth.
- Delivered Connecting Heroes and introduced Visual Labs to modernize agency operations and improve cost efficiency.
- Maintained credibility in high-stakes environments through professional, transparent communication with government clients and internal teams.
- Leveraged CRM discipline to drive accurate forecasting and data-driven territory planning.
Mid Market Account Executive
Sprint / T-Mobile
Raynham, USA
10.2010 - 04.2021
- Led GPS, mobility, and connected-technology sales for SMB and mid-market fleets, delivering telematics, workforce-management, and cloud VOIP solutions that improved visibility, safety, and operational efficiency.
- Acted as a trusted advisor to fleet, operations, and IT leaders, uncovering inefficiencies and positioning GPS tracking, driver analytics, routing, and asset-monitoring solutions that delivered measurable ROI.
- Managed full-cycle sales across transportation, construction, utilities, logistics, and field services, aligning mobility, IoT, and telematics solutions with customer business goals.
- Built strong pipelines through targeted outreach and territory planning, consistently driving new-logo acquisition and account expansion with a clear hunter mentality.
- Delivered standout performance with 187% quarterly quota attainment, 262% monthly quota, and 918 new activations during the T-Mobile/Sprint merger and COVID-19.
- Increased recurring revenue by advising customers on wireless, mobility, cloud, VOIP, and IoT solutions that improved operational efficiency and reduced costs.
- Strengthened customer loyalty by resolving issues for high-profile accounts and improving long-term retention.
- Maintained accurate forecasting and pipeline visibility through disciplined CRM management and data-driven territory execution.
Senior Account Representative
Liberty Mutual Group
Providence, USA
07.2004 - 09.2010
- Managed a growing commercial lines book, delivering proactive service, coverage guidance, and renewal strategy to drive strong retention and client satisfaction.
- Added 16 new business clients through detailed needs assessments, tailored proposals, and consultative solution recommendations.
- Achieved 95% renewal retention by building trusted relationships, negotiating competitive terms, and ensuring comprehensive coverage options.
- Ranked 5th of 19 in New Business premium in the Northeast, demonstrating strong prospecting, consultative selling, and underwriting collaboration.
- Maintained 95%+ activity levels (top 10% regionally) by consistently identifying, qualifying, and submitting high-quality commercial prospects.
- Served as the primary advisor to clients, coordinating underwriting, claims, and support resources to deliver a seamless customer experience.
- Generated high-quality referrals that fueled steady book growth and increased market penetration.
- Promoted to Senior Sales Representative for leadership, performance, and consistent achievement of sales and retention goals.
- Met or exceeded sales and service targets through disciplined account management and a client-first approach.
Loan Officer
Champion Mortgage
Boston, USA
11.2001 - 07.2004
- Originated and sold sub-prime residential loan programs through diverse lead sources and referral channels.
- Consistently met monthly unit and volume goals across all internet-based lead platforms.
- Partnered with KeyBank USA to sell equity lines and primary home loans, expanding product penetration and revenue.
- Delivered exceptional borrower support throughout the refinance process, ensuring a smooth, transparent, and high-trust experience.
Sales Specialist
Flashcom, Inc
Boston, USA
11.1999 - 04.2001
- Sold Flashcom's DSL Internet services to consumers/ business, exceeding monthly quota expectations.
- Managed outbound sales-team of five to distribute leads, generate revenue, and report results.
- Quality Assurance Team Leader: research and reconcile several thousand accounts in database to ensure correct order and billing status between Flashcom and partners (Covad Communications, Verizon).
- Worked directly with resellers of Flashcom's channel sales department and trained sales representatives on the benefits of digital subscriber lines and high-speed Internet access.
Inside Sales
Converse Inc
North Reading, USA
05.1994 - 10.1999
- Managed internal operations for major high-volume retail accounts, including Hibbett Sports and National Spirit, ensuring smooth buying, sell-through, and re-order processes.
- Developed targeted marketing and sales strategies that expanded revenue within existing accounts and generated new business opportunities.
- Supported smaller accounts across the territory through consistent communication and product guidance, increasing overall Converse sales and brand presence.
Education
Bachelor of Arts -
University of Massachusetts
Amherst05.1994
Skills
- Sales strategy and growth
- CRM proficiency
- Client partnership building
- Upselling and cross-selling
- Team collaboration
- Strategic account management
- Pipeline oversight
- Sales quota achievement
- Presentation skills
- Personal drive
Certification
Microsoft Office
Accomplishments
Winner's Circle Top Performance Award 2023
Affiliations
Volunteer - Seekonk Youth Softball Association
Timeline
Mid Market Account Executive
T-Mobile
08.2025 - Current
Enterprise Account Manager
Comcast
02.2024 - 07.2025
Enterprise Account Manager
T-Mobile
08.2022 - 09.2023
Government Account Executive
T-Mobile
04.2021 - 08.2022
Mid Market Account Executive
Sprint / T-Mobile
10.2010 - 04.2021
Senior Account Representative
Liberty Mutual Group
07.2004 - 09.2010
Loan Officer
Champion Mortgage
11.2001 - 07.2004
Sales Specialist
Flashcom, Inc
11.1999 - 04.2001
Inside Sales
Converse Inc
05.1994 - 10.1999
Bachelor of Arts -
University of Massachusetts