There are only 5021 Bahá’ís in UK against claimed to be more then 34,000. Adherents of the Baha’i Faith increased to 5,021 from 4,645 in the 2001 census. that is an annual 0.78% growth per year. Put more simply, between 37-38 new Baha’is have been added per year since 2001. I’m not sure that you can call that ‘growth’ it is slightly higher than the general population growth of 0.70% per year. Which means nobody has accepted the Bahai Faith in the last ten years except the children of Bahai parents.
One hundred years ago, ‘Abdu’l-Bahá, the son of the Founder of the Bahá’í Faith, arrived in the United Kingdom for the first of his two visits. He was 66 years old. He wasted no time in taking His Father Bahá’u’lláh’s message of peace and religious renewal to western societies. His visits were crucial in the establishment of the Bahá’í Faith in the UK. In London, ‘Abdu’l-Bahá gave public lectures at City Temple, St John the Divine in Smith Square, and elsewhere. At City Temple, he said that, “The gift of God to this enlightened age is the knowledge of the oneness of mankind and of the fundamental oneness of religion.” At St John, the translation of ‘Abdu’l-Bahá’s remarks was read by the Archdeacon of Westminster, Albert Wilberforce.