Associate Invoice Reconciliations (Media)
Read straight from Critical Mass's careers page, verified 3d ago.Seekless can tailor your résumé to it.
Seekless can write your résumé for this posting first.
Before you apply
LocationSan Jose, Costa Rica
Work modehybrid
Typefull-time
SeniorityEntry
ExperienceUp to 2 yrs
DepartmentMedia
Company size501–1,000 people
PostedSep 23, 2026 · 1mo ago
Verified live3d ago
At a glanceSummarised by Seekless from the posting.
Diploma or degree with a focus on accounting, finance, marketing, media, or a related field
0–2 years of experience in accounting, finance, media operations, or a related environment
Strong accounting knowledge complemented by solid technical and analytical skills
Strong Excel skills, including the ability to work confidently with formulas, lookups, pivot tables, and data sets
Proficiency in Microsoft Office Suite, including Excel, Word, and Outlook
Familiarity with foreign currency transactions
Exceptional attention to detail and a high level of accuracy when handling financial, campaign, and billing data
Excellent written and verbal communication skills
Strong organizational skills and the ability to manage multiple priorities and deadlines
Ability to adapt and thrive in a fast-paced, dynamic environment
Self-motivated and capable of working independently with minimal supervision
Experience with Mediaocean, Prisma, or other media planning, buying, or financial management tools is a plus
Work from an office a minimum of 3 days a week
Comfortable working in alignment with Eastern Time (ET)
Skills
Excel
Microsoft Office Suite
Word
Outlook
Mediaocean
Prisma
Benefits
Maternity leave
Parental leave
Health insurance
Vacation
Sick days
Learning and development
Employee discounts
About the role
Join Critical Mass as our Associate Invoice Reconciliations (Media) with a focus on media billing. In this role, you will play a vital part in supporting our media investment team, ensuring accurate and timely invoicing for our clients, and maintaining meticulous records of media budgets and vendor transactions. If you have a passion for media and finance, exceptional attention to detail, and thrive in a dynamic environment, we invite you to apply and become an integral part of our team.
The ideal candidate should be comfortable working in alignment with Eastern Time (ET).
You Will:
•
Maintain oversight of client media budgets and requirements and develop and communicate media billing schedules
•
Review and audit Media Authorization Forms alongside related vendor invoices.
•
Provide support for SOX Testing, including documentation and assistance with selected samples
•
Reconcile client billing and vendor invoices within the finance system
•
Manage supporting backup documentation for month-end reconciliation
•
Prepare ad hoc reports as necessary for internal and external purposes
•
Coordinate campaign timelines and provide operational support to the investment team throughout campaign activation, including actualization and vendor invoice reconciliation.
•
Assist with campaign setup, buy entry, and ongoing maintenance, ensuring all inputs align with client-approved budgets and Media Authorization Forms (MAFs).
•
Collaborate with internal teams to deliver accurate status updates for billing purposes.
•
Contribute to process improvement initiatives and support automation efforts to enhance efficiency in client and campaign deliverables.
You Have:
•
Diploma or degree with a focus on accounting, finance, marketing, media, or a related field.
•
0–2 years of experience in accounting, finance, media operations, or a related environment.
•
Strong accounting knowledge complemented by solid technical and analytical skills.
•
Strong Excel skills, including the ability to work confidently with formulas, lookups, pivot tables, and data sets.
•
Proficiency in Microsoft Office Suite, including Excel, Word, and Outlook.
•
Familiarity with foreign currency transactions.
•
Experience with Mediaocean, Prisma, or other media planning, buying, or financial management tools is a plus.
•
Exceptional attention to detail and a high level of accuracy when handling financial, campaign, and billing data.
•
Excellent written and verbal communication skills.
•
Strong organizational skills and the ability to manage multiple priorities and deadlines.
•
Ability to adapt and thrive in a fast-paced, dynamic environment.
•
Self-motivated and capable of working independently with minimal supervision.
What We Offer
•
Maternity and parental leave extra days
•
Competitive benefits packages
•
Vacation, compassionate leave, sick days, and flex days
•
Access to online services for families and new parents
•
Diversity and Inclusion Board with 12 affinity groups
•
Internal learning and development programs
•
Enterprise-wide employee discounts
•
And more…
At Critical Mass, we value our employees and offer competitive compensation and benefits packages. If you’re looking for a challenging and rewarding opportunity to make a significant impact on the lives of our employees, we encourage you to apply for this exciting position today!
About the company
The Talent Team at Critical Mass is focused on ensuring we provide the best training, onboarding, and employee experience possible! Our new hires & employees are the future of our organization, and we want to set you up for long-term success. In an effort to do so, we expect our team to work from an office a minimum of 3 days a week.
The Ask Stems From Our Want ToStrengthen opportunity for continuous learning
Improve collaboration and team relationships.
Increase employee engagement
This work model balances the need for individual flexibility while maintaining the relentless customer focus we provide at CM. We understand that not everyone may feel comfortable with this expectation, so we ask that you please let us know immediately if there are any concerns so we can help navigate accordingly.
Legal
*Critical Mass is an equal opportunity employer.
Hiring process
Critical Mass uses artificial intelligence in our recruitment process to enhance job postings, filter keywords during the review of prospective candidates, and, in some cases, transcribe interviews with our recruiters. Human review remains central to the process, and all hiring decisions are ultimately made by our team.*
The Critical Mass Talent Acquisition team will only communicate from email addresses that use the URLs criticalmass.com, omc.com and us.greenhouse-mail.io. We will not use apps such as Facebook Messenger, WhatsApp, or Google Hangouts for communicating with you. We will never ask you to send us money, technology, or anything else to work for our company. If you believe you are the victim of a scam, please review your local government consumer protections guidance and reach out to them directly.
If U.S. based: https://www.consumer.ftc.gov/articles/job-scams#avoid
If Canada based: https://www.canada.ca/en/services/finance/consumer-affairs.html
If U.K. based: https://www.gov.uk/consumer-protection-rights
If Costa Rica based: https://www.consumo.go.cr/educacion_consumidor/consejos_practicos.aspx