Accounts Payable Assistant - Stock

Mountain Warehouse is on the hunt for an Accounts Payable Assistant to join its Finance team at the London head office. The retailer runs from over 4000 stores across the United Kingdom, Europe, North America and New Zealand, and supports a strong e-commerce platform with marketplaces such as Amazon & eBay both in the UK and internationally. This role sits in a busy AP function and reports to an Accounts Payable Team Leader, helping keep supplier accounts in good order as the business grows.

The position is permanent, full time and based in London, with a hybrid approach that blends days in the office with home working. It’s a chance to contribute to a global retail business while building a career in finance within a team that supports multiple channels and expanding supplier relationships.

If you enjoy detail-oriented work, like solving supplier queries, and want a role with clear opportunities to develop in accounts payable, this could be a great fit.

A day in the life at the AP desk

You’ll manage a defined set of supplier accounts, including both UK and international partners, ensuring invoices and remittance details are up to date and queries are resolved promptly. The role also involves keeping the AP inbox under control, routing invoices for processing and addressing questions or escalating when needed.

Processing invoices and credit notes sits at the core of the job, along with setting up new suppliers, capturing bank details, remittance email addresses and payment terms while keeping supplier records accurate and complete.

You’ll perform supplier statement reconciliations, investigate outstanding balances and help with journal entries in Netsuite. You’ll review aged creditors reports and assist with payment runs to ensure approved invoices are paid on time, particularly for key accounts.

Collaboration is essential, so you’ll work with internal teams and external contacts to resolve invoice queries quickly while upholding internal controls and company policies. You’ll also contribute to AP projects, system improvements and testing, plus other ad-hoc Finance activities, and support month-end activities as part of a team working toward shared targets.

What you’ll bring to the team

Here’s what Mountain Warehouse is looking for in a candidate.

• Experience delivering accounts payable tasks, typically 1–2 years
• A clear interest in building a career in accounts payable and finance
• Strong numeracy and IT skills, with Excel highlighted as a key tool
• Excellent attention to detail and a proven track record of accuracy
• Good spoken and written communication with a proactive problem-solving mindset
• Solid organisational and time-management abilities with a knack for meeting deadlines
• An open, friendly, proactive approach and a desire to grow as part of a growing team

Pay, benefits and practical details

The role offers a competitive salary and benefits package. Mountain Warehouse supports hybrid working, with three days in the London based office and two days working from home.

The position is based at the head office in London and is permanent and full-time. Applications close on 8 October 2026.

• 50% staff discount and 25% for family and friends
• Pension scheme
• Holiday allowance

Advice for applicants

Lead with your accounts payable experience on your CV and in interviews, and show the specific AP duties you’ve handled, such as managing supplier accounts, processing invoices and setting up new suppliers.

Demonstrate your numeracy and Excel chops with concrete examples, reconciling statements, creating reports or spreadsheets that supported AP processes will help you stand out.

Be ready to discuss processing journals in Netsuite and any AP projects, system improvements or testing you’ve contributed to, since those activities appear in the role’s responsibilities.

When you interview, ask about ongoing AP projects and how this role will contribute, and inquire about the first 90 days expectations and how success is measured within the AP team.