Lead Demand Planner & Buyer for High-Growth Activewear

Thrivin; Birmingham; On-site; GBP 45,000 - 65,000; Full time

Job summary

Thrivin is a fast-growing global activewear brand operating in a high-volume ecommerce environment. As Demand Planner & Buyer, you will own the planning and buying process from sales forecasting and open-to-buy management through to purchase order placement, replenishment and inventory optimisation.

You’ll work closely with the wider product, operations and commercial teams, providing clear recommendations and insights to support trading decisions and future growth.

Qualifications

• 5+ years' experience within apparel planning, merchandising, buying or related field.
• Personally owning open-to-buy and making commercial buying decisions.
• Hands-on experience creating and placing purchase orders.
• Strong planning fundamentals: weeks of cover, sell-through, size curves, in-stock rate, margin and discounting.
• Experience with proforma invoices, MOQs, lead times and supplier follow-ups.

Responsibilities

• Own open-to-buy by category, including forecasts, receipt plans and plan vs actual.
• Run bi-weekly replenishment end-to-end from demand to PO submission.
• Determine newness buy quantities at style, colour and size level.
• Own full PO lifecycle: creation, submission, amendments and tracking.
• Manage inventory across categories with healthy stock levels and in-stock rates.
• Monitor inventory performance and identify stock risks, shortages and excess.
• Lead markdown and overstock actions to optimise sell-through.
• Analyse weeks of cover, sell-through, size curves and gross margin.
• Present planning readouts and insights during weekly/monthly trade reviews.
• Collaborate with suppliers on proforma invoices, MOQs and lead times.

Skills

Sales forecasting

Open-to-buy

Inventory management

PO placement

Excel

Data analysis

Supplier liaison

Tools

Claude Code

Claude Cowork

Job description

Thrivin is a fast-growing global activewear brand operating in a high-volume ecommerce environment. As Demand Planner & Buyer, you will own the planning and buying process from sales forecasting and open-to-buy management through to purchase order placement, replenishment and inventory optimisation.

You’ll work closely with the wider product, operations and commercial teams, providing clear recommendations and insights to support trading decisions and future growth.