A Home Office quarterly report on the policing of terrorism in the UK, published this month, said 46 of them (64 per cent) were released after serving their sentences, but would be subject to strict licence conditions, in a bid to prevent reoffending.
The other 26 released had been held on remand prior to a charge or conviction.
The report said: "A total of 72 prisoners held for terror-related and domestic extremism/separatism offences were released from custody in Great Britain in the year ending September 30 2016.
"Of these, 46 (64 per cent) were persons discharged from custody after serving their sentences, many of whom will have been released subject to meeting certain licence conditions.
"Of those released from custody, 28 of the 72 had sentence lengths of less than 4 years.
"A further 26 were not sentenced, which includes a number of persons held on remand prior to a charge or conviction."
Yousaf Bashir, Rajib Khan and Mohammed Alamgir, three of the latest jailed in UK for terror offences
But, the report said, despite the releases, that, overall that the amount of people in prison for terror-related offences is rising.
At the end of 2016, there were 183 people in custody in Great Britain in connection with terror offences – up 40 on 2015.
The report said: "Of those in custody, the majority (78 per cent) had been convicted.
"The remaining 22 per cent were being held on remand, in custody until a later date when a trial or sentencing hearing will take place."
There have been a number of other people jailed for terror-related offences already this year.
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These include five men convicted of organising and delivering terrorist speeches in Luton, Bedfordshire, in 2015.
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Of these, 46 were persons discharged from custody after serving their sentences, many of whom will have been released subject to meeting certain licence conditions.
Home Office report
They were jailed for a combined total of more than 20 years last month at the Old Bailey.
Yousaf Bashir, 36, from Luton was sentenced to four and a half years imprisonment for one count of addressing a meeting to encourage support for ISIS.
Rajib Khan, 38, from Luton was sentenced to a total of six years and six months for one count of arranging, managing or assisting in arranging or managing a meeting to support ISIS, and five years for one count of addressing a meeting to encourage support for the terror group.
Mohammed Istiak Alamgir, 37, from Luton, was sentenced to six years imprisonment for three counts of addressing a meeting to encourage support ISIS.
Mohammed Sufiyan Choudry, 23, from Maidenhead, Berkshire, was sentenced to four years imprisonment for one count of encouraging support for Islamic State.
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Ziaur Rahman, 39, from Luton, was sentenced to two and half years imprisonment for three counts of arranging, managing or assisting in arranging or managing a meeting to support the barbaric group.
Also last month Mohammed Mayow and Mohanned Jasim pleaded guilty to terror charges after being caught trying to leave the UK with terrorist literature for unknown reasons at Dover in Kent.
Mohammed Mayow, 23, from Hayes, Middlesex, and Mohanned Jasim, 21, from Southall, west London, were arrested at Dover eastern docks by police as they tried to leave the UK in November 2015.
It was unclear why they were leaving, but Mayow pleaded guilty to six counts of “distribution or circulation of a terrorist publication” and was sentenced to five years and two months’ imprisonment.
Jasim was sentenced to two years’ imprisonment after pleading guilty to “two counts of publication of a statement, and at the time of publishing, intended or was reckless as to whether members of the public would be directly or indirectly encouraged or otherwise induced by the statement to commit, prepare or instigate acts of terrorism”.