He was the eldest son of the Rev. William Betton Champneys, B.C.L. of St. John's College, Oxford, by his marriage with Martha, daughter of Montague Stable, of Kentish Town. He was born in Camden Town, St. Pancras, London, 6 April 1807, and was educated by the Rev. Richard Povah, rector of St. James's, Duke's Place, city of London, and having matriculated from Brasenose College, Oxford, on 3 July 1824, was soon after elected to a scholarship.  He took his B.A. degree in 1828, and his M.A. in 1831.
He was then ordained to the curacy of Dorchester on Thames near Oxford, whence he was transferred three months afterwards to the curacy of and St Ebbe's Church, Oxford, and in the same year was admitted a fellow of his college. In this parish he established national schools, the first that were founded in the city, and during the severe visitation of the cholera in 1832 he assiduously devoted himself to the sick. 
Later he held incumbencies at Whitechapel and St Pancras; and was a Canon of St Paul's Cathedral from1851. He was in 1837, appointed rector of St. Mary's, Whitechapel, London, a parish containing thirty-three thousand people, where, mainly through his personal exertions in the course of a short time, three new churches were built. Here also he erected schools for boys and girls, and a special school for infants; but finding that many children could not attend in consequence of being in want of suitable apparel, he set up a school of a lower grade, which was practically the first ragged school opened in the metropolis. In connection with the district he founded a provident society, assisted in the commencement of a shoeblack brigade, with a refuge and an industrial home for the boys, and co-operated with others in the work of building the Whitechapel Foundation Commercial School. He was the originator of a local association for the promotion, health, and comfort of the industrial classes, and also of the Church of England Young Men's Society, the first association of young men for religious purposes and mutual improvement which was seen in Whitechapel. 
The London coal-whippers were indebted to him for the establishment of an office, under an act of parliament in 1843, where alone they could be legally hired, instead of as before being obliged to wait in public-houses. His principles were evangelical and catholic. His sermons attracted working men by plain appeals to their good sense and right feeling. On 3 Nov. 1851, on the recommendation of Lord John Russell, he was appointed to a canonry in St. Paul's, and the dean and chapter of that cathedral in 1860 gave him the vicarage of St. Pancras, a benefice at one time held by his grandfather. 
The rectory of Whitechapel had been held by him during twenty-three years, and on his removal he received many valuable testimonials and universal expressions of regret at his departure. He was named dean of Lichfield on 11 November 1868; attached to the deanery was the rectory of Tatenhill, and his first act was to increase the stipend of the curate of that rectory from £100 to £600 a year, and to expend another 600l. in rebuilding the chancel of the church.  He died at the deanery, Lichfield, on 4 February 1875, and was buried in the cathedral yard on 9 February.
He married on 20 March 1838, Mary Anne, fourth daughter of Paul Storr, of Beckenham, Kent.  His seven children included the distinguished physician Francis Champneys, the architect and author Basil Champneys and the rowing clergyman Weldon Champneys.
- Amongst others he wrote The Path of a Sunbeam”,1845; “The Spirit of The World”, 1862; “Parish Work”, 1865 and “Things New and Old”,1869 > British Library website accessed 19:28 GMT 26 June 2012
- Boase 1887.
- OXFORD, Saturday, June 7 .Jackson's Oxford Journal (Oxford, England), Saturday, June 7, 1828; Issue 3919
- THE LONDON GAZETTE OF TUESDAY, NOVEMBER 4 . The Morning Chronicle (London, England), Wednesday, November 5, 1851; Issue 26488
- From the LONDON GAZETTE, Friday, Dec. 4.The Times (London, England), Saturday, Dec 05, 1868; pg. 8; Issue 26300
- The Late Dean Of Lichfield.-The Very Rev. William Weldon Champneys The Times (London, England), Saturday, Feb 06, 1875; pg. 5; Issue 28232
- This article incorporates text from a publication now in the public domain: Boase, George Clement (1887). "Champneys, William Weldon". In Stephen, Leslie. Dictionary of National Biography 10. London: Smith, Elder & Co.
- Fairbairn, J. S. (2004). "Champneys, Sir Francis Henry, first baronet (1848–1930)". Oxford Dictionary of National Biography. Oxford University Press. Retrieved 26 June 2012.
- Bibliographic directory from Project Canterbury
- "William Weldon Champneys", by D.J. Pound, after a photograph by John Jabez Edwin Mayall
- National Church Institutions Database of Manuscripts and Archives
|Church of England titles|
|Dean of Lichfield