He joined Ipswich Town in the summer of 2018, initially on loan before making the deal permanent in January 2019.

Born in Castries, Saint Lucia, Donacien moved to the United Kingdom with his family in 2001 at the age of eight.

He spent 5 years at Luton before spending a brief spell in the youth set up at Tottenham Hotspur, representing the club in the 2010 Milk Cup, prior to joining the Aston Villa Academy in 2010.

[18] On 31 July 2018 Donacien signed for EFL Championship side Ipswich Town, initially on loan with a view to becoming a permanent deal once he received his new UK work permit.

[20] All of his appearances during the early stages of the season came under Paul Hurst, however after Hurst was sacked in October and replaced by Paul Lambert, who had previously been the manager at Aston Villa during Donacien’s time at the club, he did not make a single appearance for Ipswich for the remainder of the season.

His transfer to Ipswich was made permanent in January 2019, signing a three-year contract for a reported fee of £750,000.

[25] He made 20 appearances for Accrington during the second half of the 2018–19 season, helping the Lancashire club secure League One safety.

Following an injury to Vincent-Young in October, he competed for a starting place in the first-team with stand-in right-back Gwion Edwards.

[28] He made his Fleetwood Town debut the following day, starting the match in a 0–0 draw with Wigan Athletic.

He quickly formed a strong partnership with new signing Wes Burns on the right-hand side of the team.

In January, Ipswich signed Harry Clarke from Arsenal, reducing Donacien's game time as a regular starter, although he still served as an important part of the squad.

[36] On 3 June 2024, Ipswich said that although the player's contract had expired, he would continue his rehabilitation throughout the off-season "and will return to pre-season training alongside the first-team squad as he builds towards a successful 2024/25 campaign".

[39] He made his debut for Saint Lucia on 16 June 2023 in a 1–3 defeat against Martinique in a 2023 CONCACAF Gold Cup qualification first preliminary round match at the DRV PNK Stadium in Fort Lauderdale, Florida.

In August 2022, Ipswich manager Kieran McKenna said of Donacien; "He certainly has the athleticism to get up and down the pitch and technically he’s growing and finding more belief in himself now.

"[41] Donacien's immigration status made national headlines in 2012 as he and his family were denied permanent residency by the United Kingdom Home Office.