The simpler route to legalise documents for Japan
Japan recognises the UK's certification system directly, which means you do not need the full embassy legalisation for Japan that many other countries require. Instead of the longer consular chain you might expect, your paperwork only needs one certification before it is considered valid. Reading Register Office can provide official certified copies of civil records if you need to keep your original documents safe. These copies carry the same status as the originals for use in Japan, and the office works by post rather than requiring an in-person visit.
This single-step certification is the most common way to legalize documents for Japan from the UK, and it is accepted by Japanese authorities including local government offices and many employers. The FCDO Legalisation Office handles this specific certification from their processing center through the mail. They will not examine content, only verify that the signature matches their records, so the style and wording must already meet what your receiving office expects in Japan.
What you need to get started
The only documents likely to be requested for Japan are UK civil records or other papers with official signatures. If you need document legalization for Japan, begin with a fresh certified copy from Reading Register Office if your paper is a birth, marriage or death record. This approach lets you send the certified version instead of your only original. The Reading office can post the copy directly to the FCDO Legalisation Office on your behalf, keeping your original safe at home.
If your paper came from somewhere else in the UK, such as a degree certificate or a company document, check first whether the Japanese authorities will accept a simpler route. Even when consular legalization for Japan is not required, the Japanese side might still insist on seeing not just a plain copy but a fresh document issued within their specified window.
Getting it done within your deadline
Regular service takes seven to ten working days for completion at the FCDO Legalisation Office once they receive your paperwork. If you need embassy attestation for Japan to happen more quickly, they also provide an express option of two to three working days. The office does not have a public counter, so all work is done by post or secure delivery, and the time it takes for post each way adds to the total timeline. Starting with the register office copy saves time later by avoiding errors that come from sending the wrong version or form.
While full embassy legalization for Japan from Reading would involve more steps and weeks of work, the actual process required for Japan moves much faster once you have everything ready. Both the FCDO and the register office are experienced with these papers and turn them around within their published schedules. Plan for postal time in both directions, though, since the legalisation office receives thousands of applications each month from across the country.