
IR35 determination is a critical process for contractors and limited companies to assess their tax status. At Business At, we provide specialist IR35 status assessments in Southampton to help you comply with HMRC regulations, avoid penalties, and ensure your contracts are properly classified.
As certified chartered accountants, we combine an automation-focused approach with extensive experience in contractor taxation. Available 7 days a week, we offer real-time answers and proactive advice to keep you compliant and confident.
Experience


Our IR35 determination process involves a detailed review of your contracts, working practices, and business structure. We assess whether you fall inside or outside IR35, providing clear, written reports that help you make informed decisions.
We leverage automated tools to cross-reference HMRC guidelines, ensuring accuracy and efficiency. This proactive approach saves time and reduces the risk of costly HMRC investigations or back taxes.
Experience
Let us take care of the hard work — so you can enjoy the rewards of a successful career.
We assist you in planning for a successful , fulfilling and prosperous future.
Beyond initial assessment, we offer ongoing support to manage your IR35 compliance effectively and sustainably.
Contract review and negotiation advice to maintain outside IR35 status
Regular status checks and updates based on legislative changes in Southampton and UK-wide
Assistance with HMRC enquiries and dispute resolution, leveraging our certified expertise
Integration with your cloud accounting and payroll systems for seamless compliance
Training for your team on IR35 best practices and proper documentation
Experience

Experience
Unlike general accountants, we specialize in IR35 determination with an innovative, automation-focused approach. Our whole-business review ensures you get tailored solutions that fit your specific needs in Southampton.
With our international network and UKAN membership, we provide government-backed support and real-time availability. Clients trust us for our proactive advice, fixed fees, and partnership model that prioritizes your growth.
Experience
Experience

“Sash has been extremely knowledgeable and reliable from when I first met him regarding helping me with my accounts as a director of a limited company for the first time. He has provided me with sound advice and helped me to understand the ins and outs of timely and successful accounting and made it easy."
Adam Garnett
We build growth-focused partnerships with every client, offering hands-on guidance through business transitions and tax complexities. Your dedicated accountant provides proactive advice when you need it most.
Clients value our availability and expertise, telling us they finally understand their numbers and feel confident expanding globally. That's the impact of innovative, responsive accountancy.
Let's Connect
Call us at +44 7795 226823 or email [email protected] anytime. We're available outside normal hours for real-time assistance. Use our contact form for quick follow-ups, and we'll reply promptly.
Start with a free, no-obligation consultation to explore your options. We'll discuss your business needs, share insights on automation or tax savings, and outline how we can partner for growth. It's easy and straightforward to take the first step.
Common questions about our IR35 determination services:
IR35 determination assesses whether a contractor should be taxed as an employee or self-employed. It's vital to ensure HMRC compliance, avoid unexpected tax bills, and protect your business status. Our Southampton-based service provides localized expertise to navigate these rules.
We offer transparent, fixed-fee packages starting with a free consultation. Costs depend on contract complexity, but we focus on value with no hidden charges. Contact us for a personalized quote tailored to your situation.
Yes, we provide full support for HMRC challenges, including evidence preparation, representation, and resolution strategies. Our experience and certification help defend your status effectively and minimize disruptions.
Absolutely. We provide regular reviews and updates to ensure continued compliance as laws or your contracts change. This proactive service is part of our partnership approach, keeping you secure and informed.

Business Accounting and Tax Ltd provides automation-focused accounting, tax, and international services for small to medium businesses in Southampton and beyond. Contact us for a free consultation to grow your business.
73 Holly Hill, Southampton, SO16 7ES, Hampshire, United Kingdom
+447795226823
Business Accounting & Tax Ltd is a Limited Company with Registered Company Number 07894977
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