Just in case anyone misunderstands, The Deed Poll Office is a commercial venture, and has no official status (in fact there is no official body). There is nevertheless a lot of useful information on their website.
Good point, Peter. I ought to have said it was their advice on research and history I was referring to.
There is, of course, an official body for enrolling deeds poll. That route must now be almost compulsory, if you want the name change to have full effect. Enrolment is done by the King's Bench division of the high court, who also produce the
DIY document set for doing it.
And it only costs £42.44 - plus two solicitor's fees for administering oaths - but has not been exactly popular. I've looked again at the number of hits in the Gazette using that simple search. Half of those since digitisation started (about 13,000), were in the last five years. Before 2000 it's about 300 per year, sometimes a lot fewer. That number is typical (though it fluctuates a lot) right back to WW1 (13,257 in 80 years). The few hits before that are not notices of enrollment, since that only began in 1914. So it really was very rare until the last few years, and still is rare.
Oddly, the current regulations say
These Regulations shall govern the enrolment in the Central Office of the Supreme Court of deeds evidencing change of name (referred to in these Regulations as “deeds poll”).
Thar was issued in 1994, by the "Supreme Court of England and Wales". The new Supreme Court of the UK was set up in 2009, so presumably that text should have been amended to the "Senior Courts of England and Wales".