Strategic Demand Planner & Buyer for Activewear Ecommerce

Thrivin; Hawton; On-site; GBP 42,000 - 64,000; Full time

Job summary

Thrivin, a fast-growing global activewear brand, is seeking an experienced Demand Planner & Buyer to own planning, purchasing and inventory across the business. You’ll balance availability, inventory health and commercial performance with hands-on execution.

You’ll manage open-to-buy, replenishment cycles, PO lifecycle and supplier coordination, driving data-driven decisions in a high-volume ecommerce environment as Thrivin scales internationally.

Qualifications

• 5+ years' experience in apparel planning, merchandising, buying or a closely related field.
• Experience owning an open-to-buy and making commercial buying decisions.
• Hands-on experience creating and placing purchase orders.
• Advanced proficiency in Excel and data analysis with large datasets.
• Strong supplier-facing experience with proforma invoices, MOQs, lead times and order chasing.

Responsibilities

• Own the open-to-buy by category, including sales forecasts, receipt plans and monthly plan vs. actual performance.
• Run the bi-weekly replenishment cycle end-to-end from demand analysis to PO submission.
• Determine newness buy quantities at style, colour and size level to align with launches.
• Own the full purchase order lifecycle—from creation to invoicing and ETA tracking.
• Manage inventory across categories, maintaining stock levels and in-stock rates.
• Monitor inventory performance and identify stock risks, shortages and excess inventory.
• Lead markdown and overstock actions to optimise sell-through and health.
• Analyse weeks of cover, sell-through, size curves, gross margin and discount rate.
• Present planning insights during weekly and monthly trade reviews.

Skills

Planning & buying decisions

Open-to-buy management

Supplier management

Data analysis

Forecasting

Tools

Claude Code

Claude Cowork

Excel

Job description

Thrivin, a fast-growing global activewear brand, is seeking an experienced Demand Planner & Buyer to own planning, purchasing and inventory across the business. You’ll balance availability, inventory health and commercial performance with hands-on execution.

You’ll manage open-to-buy, replenishment cycles, PO lifecycle and supplier coordination, driving data-driven decisions in a high-volume ecommerce environment as Thrivin scales internationally.