Full-Time Office & Finance Assistant

Custom Media KK

Custom Media is an award-winning integrated marketing agency based in central Tokyo. We are seeking a reliable, detail-oriented, and proactive Finance & Office Assistant to support our financial operations and office administration.

This is a hybrid role suited to someone who enjoys variety, takes ownership of their work, and can manage both numbers and day-to-day office coordination with confidence.

The Job:
This position supports both finance operations and office/administrative functions. The role is hybrid, requiring at least two days per week working from our Kamiyacho office. The ideal candidate will be a native Japanese speaker with a good command of English and over three years of office administrative experience.

Job Description:

Key Responsibilities

Finance & Accounting Support

• Manage Accounts Payable and Accounts Receivable, including:

• Processing vendor invoices and payments in coordination with our outsourced accounting partner

• Issuing and processing client invoices

• Assist with bank and account reconciliations

• Handle staff expense claims and manage petty cash reporting

• Provide general administrative support to the finance function, including filing, documentation, and responding to internal inquiries

• Support day-to-day financial operations as needed

Office Administration & HR Support

• Manage incoming and outgoing communications, including phone calls and postal mail

• Maintain office supplies inventory and coordinate ordering

• Support HR-related administration, including:

• Coordinating onboarding processes for new hires

• Liaising with the outsourced accounting firm on HR documentation (health insurance, pension, etc.)

• Assisting foreign employees with visa-related document preparation

• Run office-related errands when required (e.g., bank, tax office, law office)

Qualifications and Experience:

Experience & Education

• Bachelor’s degree

• 3+ years of relevant experience in finance administration, office administration, or a similar role

• Experience working in a multicultural environment is highly valued

Skills & Competencies

• Language: Native Japanese fluency is essential, with a good command of English

• Organization & Accuracy: Strong attention to detail, excellent numeracy, and the ability to prioritize and manage multiple tasks

• Technical Skills: Proficiency in Microsoft Office and Google Workspace, Strong Excel skills (VLOOKUPs and Pivot Tables are a plus), Experience using accounting software

Work Style:

• Proactive, flexible, and quality-oriented

• Able to work independently while collaborating effectively with the team

• Positive and constructive under pressure

• Team Fit

• A collaborative team player who is open to feedback and willing to share ideas

• Professional, dependable, and service-minded

Working Hours:

• 9:30am to 6:30pm, Monday to Friday

• Work from home and / or office flexibility

• Holidays: Saturdays and Sundays, National Holidays and Paid Vacation

Why Join Us?

• Be part of a dynamic, collaborative multicultural team

• Enjoy a flexible, hybrid/remote work environment.

• Opportunities for professional growth and continuous learning.

• Attractive salary negotiable based on experience.

• Transport allowance, work from home allowance.

• Paid vacations, social insurance and benefits.

• The company will provide laptop with required software.

• Friendly, comfortable environment at a central office in Kamiyacho.

How to apply:
Please apply with a cover letter to careers@custom-media.com explaining why you are the right person for this position.

Our agency is an Equal Opportunity Employer. We celebrate diversity and are committed to creating an inclusive environment for all employees.