Patent Box in 2026: Start the Year with a Plan

As you plan for growth in 2026, it helps to get things right from the start.

One area of tax relief that’s often overlooked is the Patent Box, a generous innovation tax incentive, particularly now that the gap between the main Corporation Tax rate and the Patent Box rate has widened.

With Corporation Tax at 25% and the Patent Box rate still at 10%, keeping and commercialising intellectual property in the UK can give your business a real strategic edge.

Here are five practical reasons why 2026 is a great time to revisit the Patent Box, along with tips to help you start the year strong.

1 | Planning early for the nexus fraction really matters

The Patent Box operates under a mandatory “nexus approach”, which links the level of tax relief available to where and how the underlying R&D was carried out.

Put simply, to get the full benefit, most of the development work for the patent should be done in-house. If you outsource R&D, less of your profits may qualify for the 10% rate.

This means Patent Box planning isn’t just about patents, it’s also about:
✔  where R&D activity takes place
✔  how it’s structured
✔  and how costs are tracked over time

If you consider this early, you can decide whether to keep important development work in-house, especially for projects that might lead to patentable IP.

2 | The two-year election window is strict, and easy to miss

One of the most common reasons businesses lose Patent Box relief is simply timing. There is a non-negotiable two-year deadline to elect into the Patent Box, starting from the end of the accounting period in which the relevant profits arise. If the election isn’t made in time, the relief for that period is lost permanently.

There’s no discretion and no late submission route. If you’re getting ready to commercialise your innovation, planning ahead is crucial. Knowing when profits will come in and when to make elections helps you avoid costly mistakes that can’t be fixed later.

3 | Group acquisition rules can unlock earlier access to relief

While the Patent Box generally rewards in-house R&D, there are specific rules that apply where IP is acquired as part of a group restructure or intra-group transfer.

Handled correctly, these rules could allow you to access Patent Box relief sooner on IP that was developed by another entity within the same corporate group, as long as you meet the right conditions.

This is particularly relevant for groups that:

• centralise IP ownership
• restructure ahead of commercial launch
• or move assets between entities for commercial reasons

Understanding these nuances early allows Patent Box considerations to be built into wider group planning, rather than treated as an afterthought.

4. Patent Box and R&D tax credits work best together

People often discuss Patent Box relief and R&D tax credits separately, but in reality, they are closely connected.

The same R&D expenditure that supports an R&D tax credit claim is also used to calculate the nexus fraction for Patent Box purposes. This makes consistent data capture and cost tracking critical.

Treating these regimes in isolation often results in missed opportunities to optimise both reliefs. An integrated approach, where R&D costs, project records, and IP strategy are aligned, makes it far easier to claim both incentives effectively and defensibly.

5. Preparing for patent filings in a changing IPO landscape

A practical note for 2026: the Intellectual Property Office is moving to its new One IPO digital service.

If you plan to file patents this year, make sure your internal processes match the new platform. Delays in getting patents granted can cause problems, since you need a granted patent to use the Patent Box.

Getting filings right first time, and avoiding administrative delays, helps keep Patent Box timelines on track.

Evergreen best practice: treating IP as a business asset

Beyond the mechanics, the strongest Patent Box outcomes tend to come from businesses that treat IP as a core business asset, not just a legal formality.

That means:

→  recognising patents, designs, and know-how as drivers of long-term value

→  planning patenting outcomes alongside R&D activity

→  and being mindful that where R&D is carried out directly affects future tax relief

The Patent Box rewards the commercialisation phase, while R&D tax credits support development. Used together, they can form a powerful, long-term approach to funding innovation, but only when they’re planned for early.

If you have any questions about Patent Box or IP Planning, please contact the ABGi Team. We’ll get back to you to discuss your unique needs and explain how we can assist.