London · Kyiv
Accounting, tax and advisory for Ukrainian businesses growing in the UK, and for international companies doing business in Ukraine.
Personal care Ukrainian roots AI-empowered
Statutory, management and IFRS accounts, prepared on time.
UK corporation tax, VAT and cross-border structuring.
Fractional CFO support, forecasting and investor reporting.
UK and Ukrainian entities set up and kept compliant.
Who we are
XI Squared is a boutique financial advisory firm specialising in cross-border finance between Ukraine and the United Kingdom. We help Ukrainian businesses set up and grow in the UK, and we help international investors and companies do business in Ukraine.
To help Ukrainian businesses operate confidently in the UK, and to help international capital engage Ukraine with clarity and trust.
To be the most trusted boutique financial advisory firm between Ukraine and the UK, known for senior expertise, Ukrainian depth and modern execution.
We do not compete on scale. We compete on focus, depth and authenticity.
What we do
Our work follows the way money and companies actually move between Ukraine and the UK: going out, operating abroad, and coming in.
A correct legal and financial footing from the first day of your UK operations.
The monthly and annual work that keeps a growing international company in good order.
Financial and regulatory clarity for companies and investors taking part in Ukraine's rebuilding.
How we work
Personal first. Ukrainian roots as the difference. Modern technology as the edge.
You always work with a principal or senior expert, never a ticketing system or a revolving cast of junior staff. The same people from the first conversation through years of partnership, with direct access to the founder.
Founder-led Ukrainian knowledge paired with fluency in UK financial and regulatory frameworks. We work in Ukrainian and English, and we understand both business cultures from the inside.
Modern AI-assisted systems give faster reporting, sharper accuracy and more proactive advice than firms running on legacy tools. You feel it as quicker answers and earlier insight, never as automation in place of a person.
The principal promise
Always a principal.
Never a ticket.
Every engagement is led directly by a principal or senior expert. The person you meet in the first conversation is the person who handles your accounts, your tax and your questions years later. No ticketing systems, no junior handoffs.
Our services
One firm that can set up your entity, run your accounts, file your taxes, manage payroll and advise at CFO level.
One firm. One principal. Every discipline.
Most boutiques specialise narrowly: accounting only, tax only, or CFO only. XI Squared brings the full financial stack under one trusted relationship. Our advisors have led these functions inside operating companies, not only advised on them from outside.
Why XI Squared
Real Ukrainian roots, real UK regulatory depth and modern systems, delivered personally by senior advisors.
Strong capability, but you are passed between teams and rarely speak to someone who knows the Ukrainian side of your business.
Good understanding of Ukraine, but often without UK regulatory depth or modern reporting systems.
Ukrainian fluency and UK expertise in the same person, supported by AI-assisted systems. Same names, every call.
Sector expertise
We have advised businesses in these sectors for years, managing their statutory reporting, tax and cross-border structuring through each stage of growth. That continuity gives us a working command of each sector's margins, cost structures, regulatory obligations and reporting cycles.
Revenue recognition for subscription models, R&D tax relief claims, EIS/SEIS advance assurance and investor-grade reporting for funding rounds.
Export-led businesses in timber, granite, mining and energy: transfer pricing, double tax treaty planning, FX exposure and trade finance.
Acquisition and holding structures for UK and Ukrainian property, capital gains planning, rental income reporting and ongoing compliance.
Contract accounting for long-term and government engagements, cost allocation, regulatory compliance and audit readiness in Ukraine.
Brokerage businesses handling imports and exports in Ukraine: customs duties and import VAT, brokerage fee income, client settlement accounts and FX on cross-border payments.
About XI Squared
XI Squared was founded by Mariia Prokopchuk to give Ukrainian businesses the kind of senior, bilingual financial partner they need when they expand into the UK. Four years on, the firm serves clients in technology, natural resources, real estate and security.
Mariia brings 18 years of accounting experience and a master's degree in Accounting and Audit. She has worked with clients of every size, from self-employed founders preparing their first accounts to companies with more than 3,000 employees, and on work ranging from new business setup to complex government contracts. Her approach is proactive and exact: keep the records right, explain what the numbers mean, and help each client make informed decisions as the business grows.
We combine deep knowledge of Ukraine, working fluency in UK regulation, and modern AI-assisted systems that make reporting faster and more accurate. You get the precision of the tools and the judgement of a senior advisor.
XI Squared continues the practice Mariia built as Phoenix International Finance: the same people, the same principles and the same commitment to clients, under a new name.
Mariia ProkopchukFounder & Principal
Connect on LinkedIn →Insights
After four years building XI Squared, Mariia Prokopchuk explains why she is committing to the firm full-time, and what it means for clients.
Read the article →Entity choice, banking, VAT and the first year of filings.
The financial and regulatory questions to answer first.
Bridge. Build. Grow.
Tell us where your business is today and where you want it to be. A principal will reply within one working day.
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