HMRC ran over 300,000 tax enquiries in a single year. For globally mobile HNWIs, the consequences of a weak residency position are significant.

Most rely on spreadsheets and boarding passes to evidence their tax residency. Neither holds up under investigation scrutiny.

Daysium is built for that gap.

Our platform codes actual tax rules across 17 jurisdictions, giving HNWIs and their advisors real-time day counts alongside contemporaneous, geotagged records built to withstand tax authority scrutiny worldwide.

This is not a day-counting app. It is the execution layer between tax advice and compliance.

When the enquiry letter arrives, Daysium clients can say with confidence: "There's nothing to see here — everything is in order."

Shortlisted for UHNW Private Client Services of the Year at the 2026 Citywealth Magic Circle Awards. Selected for the Rathbones Inspire Programme. Backed by Google for Startups. Advised by Paul Aplin OBE — over 40 years at the heart of UK tax practice.

Our Partner Programme is open to tax advisors, wealth managers, and financial services professionals. Find out more at daysium.com.

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