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- Tasks: Help new sellers onboard smoothly onto our marketplace platform.
- Company: Join a leading retailer with a commitment to inclusivity and support.
- Benefits: Enjoy discounts, flexible working, and a range of wellbeing perks.
- Other info: Dynamic role with opportunities for growth and development.
- Why this job: Make a real impact by guiding sellers to success in the marketplace.
- Qualifications: Experience in ecommerce and strong communication skills are essential.
The predicted salary is between 30000 - 40000 £ per year.
The Seller Onboarding Assistant is responsible for delivering a seamless, efficient and accurate onboarding experience for new Marketplace Sellers onto the Marketplace back‑office platform. This role ensures all technical integrations, operational onboarding tasks and catalogue uploads are completed to a high standard, enabling Sellers to go live successfully and deliver great product choice and service for customers.
What I am accountable for:
- The end‑to‑end onboarding journey for new Sellers, ensuring all required tasks (including KYC), documentation and compliance checks are completed accurately and on time.
- Guide Sellers through account setup, supporting them to configure their store, policies, VAT details, shipping methods and operational settings in line with business standards.
- Coordinate and validate all technical integrations, including API connections, feed uploads and order management workflow testing.
- Support Sellers to prepare, format and upload product catalogue data, ensuring compliance with taxonomy, content standards and listing quality expectations.
- Proactively identify onboarding risks or blockers, resolving issues through established processes or escalation to technical teams where required.
- Provide clear communication to internal teams regarding Seller readiness, go‑live timelines and any operational considerations.
- Maintain accurate onboarding status tracking and produce regular progress updates for the Marketplace Seller Success & Onboarding Manager.
- Continuously review and improve onboarding processes, identifying opportunities to simplify and standardise ways of working.
- Deliver a strong seller experience, providing guidance, training and resources to help Sellers feel confident and supported throughout the onboarding journey.
Key Performance Measures:
- Seller onboarding completion rates and time‑to‑live.
- Integration success rate and average time to resolve integration issues.
- Compliance and quality metrics for new listings.
- Reduction in onboarding‑related support tickets.
What I need to know:
- Experience working within ecommerce, marketplace operations or seller/vendor management.
- Understanding of product catalogue structures, data quality standards and taxonomy.
- Ability to troubleshoot technical issues related to APIs, feed integrations or backend platforms.
- Strong organisational skills with the ability to manage multiple onboarding workstreams simultaneously.
- Excellent communication skills and ability to support a wide range of external partners.
- High attention to detail and comfort working with spreadsheets, data templates and validation tools.
- Experience working directly with Mirakl Marketplace or similar marketplace platforms.
- Familiarity with digital content standards, SEO principles or marketplace listing optimisation.
- Experience in a retailer or large‑scale commercial environment.
- Knowledge of seller compliance processes (KYC, VAT validation, product safety, etc.).
Benefits:
We are committed to being a truly inclusive retailer so you’ll be welcomed whoever you are and wherever you work. We also recognise and celebrate colleagues when they go the extra mile and, where possible, offer flexible working. When you join our team, we’ll also offer you an amazing range of benefits. Starting off with colleague discount, you'll be able to save 10% on your shopping online and in‑store at Sainsbury's, Argos, TU and Habitat, and we regularly increase the discount to 15% at points during the year. We've also got you covered for your future with our pensions scheme and life cover. You'll also be able to share in our success as you may be eligible for a performance‑related bonus of up to 5% of salary, depending on how we perform. Your wellbeing is important to us too. You'll receive an annual holiday allowance and you can buy up to an additional week's holiday. We also offer other benefits that will help your money go further such as season ticket loans, cycle to work scheme, health cash plans, salary advance (where you can access some of your pay before pay day) as well as access to a great range of discounts from hundreds of other retailers. And if you ever need it there is also an employee assistance programme. Moments that matter are as important to us as they are to you which is why we give up to 26 weeks’ pay for maternity or adoption leave and up to 4 weeks’ pay for paternity leave.
Seller Onboarding Assistant in London employer: Sainsbury's Supermarkets Ltd
Contact Detail:
Sainsbury's Supermarkets Ltd Recruiting Team
StudySmarter Expert Advice 🤫
We think this is how you could land Seller Onboarding Assistant in London
✨Tip Number 1
Network like a pro! Reach out to people in the industry, attend events, and connect with potential colleagues on LinkedIn. We all know that sometimes it’s not just what you know, but who you know that can help you land that Seller Onboarding Assistant role.
✨Tip Number 2
Prepare for interviews by practising common questions related to ecommerce and marketplace operations. We suggest you come up with examples from your past experiences that showcase your problem-solving skills and attention to detail, especially when it comes to onboarding processes.
✨Tip Number 3
Showcase your tech-savviness! Familiarise yourself with tools and platforms relevant to the role, like Mirakl Marketplace. We recommend you even try to get hands-on experience if possible, as this will give you an edge during interviews.
✨Tip Number 4
Don’t forget to apply through our website! It’s the best way to ensure your application gets noticed. Plus, we love seeing candidates who are proactive about their job search. So, go ahead and hit that apply button!
We think you need these skills to ace Seller Onboarding Assistant in London
Some tips for your application 🫡
Tailor Your Application: Make sure to customise your CV and cover letter for the Seller Onboarding Assistant role. Highlight your experience in ecommerce and marketplace operations, as well as any relevant skills that match the job description. We want to see how you can bring value to our team!
Showcase Your Communication Skills: Since this role involves guiding Sellers through the onboarding process, it's crucial to demonstrate your excellent communication skills. Use clear and concise language in your application to show us you can effectively support a wide range of external partners.
Highlight Attention to Detail: This position requires a high level of attention to detail, especially when it comes to compliance and data quality. Make sure to mention any experiences where you've successfully managed multiple tasks while maintaining accuracy. We love candidates who can juggle responsibilities without missing a beat!
Apply Through Our Website: We encourage you to apply directly through our website for the best chance of success. This way, we can easily track your application and ensure it gets the attention it deserves. Plus, it’s super easy to do!
How to prepare for a job interview at Sainsbury's Supermarkets Ltd
✨Know Your Onboarding Process
Familiarise yourself with the end-to-end onboarding journey for new Sellers. Understand the key tasks involved, such as KYC checks and catalogue uploads, so you can confidently discuss how you would ensure a seamless experience.
✨Showcase Your Technical Skills
Be prepared to talk about your experience with technical integrations, especially if you've worked with APIs or marketplace platforms like Mirakl. Highlight any troubleshooting skills you have, as this role requires resolving integration issues efficiently.
✨Demonstrate Strong Communication
Since you'll be guiding Sellers through the onboarding process, practice articulating complex information clearly. Think of examples where you've successfully communicated with external partners or resolved issues through effective dialogue.
✨Highlight Your Organisational Skills
This role involves managing multiple onboarding workstreams simultaneously. Prepare to share specific examples of how you've organised tasks in previous roles, ensuring that you meet deadlines while maintaining high attention to detail.