The Pi Pen 2025

Onoto

£475

Designed for mathematicians, engineers, and collectors alike, this exclusive new edition of the Pi Pen brings a fresh perspective to a timeless classic. Now available in a rich cocoa brown finish with a subtle pearlescent glow, this exquisite fountain pen embodies both sophistication and precision.Crafted from high-quality acrylic and adorned with sterling silver fittings, it retains the signature design of Pi Pen. The cap and barrel are meticulously engraved with 314 digits of π, celebrating the infinite beauty of this legendary irrational number.Limited to 25 pieces only.

Onoto's own words, read from their page on 2026-09-01.

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Where this comes from

The part other shops don't tell you. Three separate questions, kept separate on purpose, each with its source.

UK company
Registered at Companies House as THE ONOTO PEN COMPANY LIMITED, number 03744683. Checked 2026-08-29.
Means the business is a British legal entity, not a British-sounding name owned elsewhere. It says nothing about where anything is made.
UK operations
Not yet checked.
Means people employed here, or premises they actually work from. We keep this separate from the company badge because a registered office can be an accountant's spare room, and a company can be registered in Britain while everything it does happens somewhere else. Where we have not looked, we say so rather than assuming.
Where it is made
The maker doesn't say, so neither do we.
This is about the individual product, not the company. A British firm can sell things made abroad, which is normal and not a criticism. We would rather tell you which is which than average them into a score.