Unhalfbricking is the third studio album by the English folk rock band Fairport Convention and the first of two albums released by the band in 1969. It is seen as a transitional album in their history and marked a further musical move away from American influences towards more traditional English folk songs that had begun on their previous album, What We Did on Our Holidays and reached its peak on the follow-up, Liege & Lief, released later the same year.

The album features several Bob Dylan songs, which he had not yet released. It also features Sandy Denny's signature song "Who Knows Where the Time Goes?", which was subsequently covered by many other performers and is now regarded as a classic. The only traditional song on the album, "A Sailor's Life", is seen as pivotal in the development of English folk rock music.

Changes in the line-up of the band, due not only to its musical direction but also to external events, mark this album as a turning point in the band's history. 1969 was a prolific year for Fairport Convention; from What We Did on Our Holidays to Liege & Lief within twelve months represented a major development.

The album also gave the band their first UK chart success, reaching number 12 in the UK album chart (the second highest position in the band's entire career), while the single release, "Si Tu Dois Partir", achieved number 21 in the UK singles chart.

Fairport Convention had been invited to Bob Dylan's London music publishers to hear then-unreleased tracks from The Basement Tapes sessions. The band's bassist, Ashley Hutchings, said "We loved it all. We would have covered all the songs if we could." In the event, versions of "Percy's Song", "Million Dollar Bash" and "If You Gotta Go, Go Now" (retitled "Si Tu Dois Partir") were used on the album. The French lyrics for the latter were created during the interval of a performance at the Middle Earth Club. According to guitarist Simon Nicol: "I think the boredom factor was one of the reasons we came up with this wacky idea. Three or four punters joined us in the dressing room; they were either French visitors or students of French working in London, and happened to be there that night." "Percy's Song" and "Million Dollar Bash" had never been released before.

The band's male vocalist Iain Matthews left during the recordings for Unhalfbricking to make his own album Matthews' Southern Comfort, after recording just one track, "Percy's Song". Sandy Denny sang lead vocals on all the other songs, including her own compositions, "Autopsy", and "Who Knows Where the Time Goes?". The latter was covered by many artists and is now viewed to be a classic. The lengthy "A Sailor's Life", a traditional English folk song collected by A. L. Lloyd, was already part of Denny's club repertoire. In particular, the version on Unhalfbricking has been described as "the turning point of Fairport's history from earlier contemporary Americana to English songs" and by AllMusic's Richie Unterberger as a "clear signpost to the future".

Guitarist Richard Thompson contributed two compositions to the album. The opening track, "Genesis Hall", is a slow 3/4 waltz, on which Simon Nicol played dulcimer, while Sandy Denny provided the vocals; it was the B-Side of the single release. Genesis Hall was the nickname of the former Bell Hotel in Drury Lane, which had become a squat in early 1969 and later became noted for a mass eviction by the police. In the view of Mojo magazine reviewer Mike Baines, "Thompson's writing reached maturity on 'Genesis Hall'". "Cajun Woman", which opens the second side of the album, features Dave Swarbrick's fiddle-playing in his first work with Fairport; having no electric pick-ups, the band improvised by smashing open a telephone and attaching the microphone to the instrument with an elastic band.

The title arose from the band playing the word game Ghost while travelling to and from gigs. Its object was to "avoid completing a real word", and "Unhalfbricking" was Sandy Denny's creation.