The 54-year-old attacked them at a friend's home in Hertfordshire in April 2022 after a night at the pub.
The trial heard he bought food, alcohol and cigarettes from a petrol station in the early hours, including a bottle of vodka which the victims drank.
Alford had intercourse with the 14-year-old in the garden and a downstairs toilet, and inappropriately touched the 15-year-old while she was half asleep on a sofa.
The older girl said she felt "absolutely sick" and planned to keep it a secret but had a "mental breakdown" to her friend's mother days later.
Alford told the jury the charges were a "set up" and the girls were "going to extort money from him".
The former actor rose to fame in BBC children's show Grange Hill before starring in hit ITV firefighting drama London's Burning in the 1990s.
He denied four counts of sexual activity against the younger girl and sexual assault and assault by penetration of the 15-year-old.
However, he was found guilty at St Albans Crown Court in September.
When the verdicts were read out, he put his head in his hands, shouting "wrong, I didn't do this".
All of the offences happened at the home of a third girl, whose father was friends with Alford.
The jury was shown a video of the 14-year-old's police interview in which she said she'd never had sex before the attack.
She told officers: "I told him to stop because I didn't want to have sex with an old man."
The younger girl said in a victim statement read on her behalf that the assault "affected me and my family in every way".
The older girl said Alford had "destroyed my mental wellbeing".
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Alford shook his head as recorder Caroline Overton outlined the offences before sentencing him at St Albans Crown Court on Wednesday.
Chris White, from the Crown Prosecution Service, said the disgraced star was "fully aware of the girls' ages, yet he chose to exploit them".
Alford - whose real name is John Shannon - must serve two-thirds of his sentence in custody and the rest on licence.
Alford was previously jailed for nine months in 1999 for supplying drugs to the News Of The World's "fake sheikh".
He later sued the paper over claims it tapped his phone and hacked his voicemail and received £500,000 compensation.
On Wednesday, Kamran Ahmed, Heba Muraisi and Lewie Chiaramello announced their decision to end their hunger strikes as Elbit Systems UK failed to win a government contract.
Prisoners for Palestine said that Elbit Systems had lost out on a £2 billion contract that would have seen them train 60,000 British troops a year.
The campaign group said in a statement: "Our prisoners hunger strike will be remembered as a landmark moment of pure defiance; an embarrassment for the British state.
"Banning a group and imprisoning our comrades has backfired on the British state, direct action is alive and the people will drive Elbit out of Britain for good."
All the hunger strikers have been detained in prison on remand while they await trial for alleged break-ins or criminal damage carried out in the name of Palestine Action before the group was banned under terrorism legislation.
By the time they are tried, all will have spent more than a year in custody.
A judicial review challenge to the proscription has concluded with judges reserving their decision until a later date.
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Shabana Mahmood told MPs a review by a police watchdog into the force showed "confirmation bias" over the decision to ban Maccabi Tel Aviv supporters from attending the match at Villa Park in November.
Ms Mahmood also expressed frustration that she was not able to sack Chief Constable Craig Guildford herself.
The home secretary does not have the power to hire or fire chief constables as this is now held by elected police and crime commissioners (PCCs) - a role being scrapped by the government.
Ms Mahmood said new statutory powers are planned to allow a home secretary to force the resignation of chief constables on the grounds of their performance.
West Midlands Police has said it will take "immediate action" to rectify problems raised by the police watchdog.
In a statement, the force said it had "received a copy of the preliminary review today and acknowledge that this recognises the unintentional nature of our errors. We are extremely sorry for the impact these have had on individuals and their communities".
"We are taking immediate action to address the matters raised in these preliminary findings. We know that mistakes were made but reiterate the findings that none of this was done with an intent of deliberate distortion or discrimination.
"West Midlands Police is an anti-discriminatory organisation and our planning for this football match was always about public safety of all communities.
"We continue to focus on protecting the public of West Midlands and improving our services, as we have done relentlessly during the last several years.
"We will now work tirelessly to rebuild confidence in West Midlands Police."
Meanwhile, Simon Foster, the PCC for West Midlands Police, stopped short of firing CC Guildford, saying after Ms Mahmood's statement in the Commons that the watchdog's review must be given "careful and detailed consideration".
He said he would ask questions of the force's top officer himself at a public meeting of his Accountability and Governance Board on 27 January.
"It is vital that all involved act in accordance with due process and the law at all times," he added.
What does the report say?
Speaking in parliament, Ms Mahmood outlined the key contents of the report, written by Sir Andy Cooke, the Chief Inspector of Constabulary.
The cabinet minister said: "The force, we now discover, conducted little engagement with the Jewish community, and none with the Jewish community in Birmingham before a decision was taken.
"Andy describes an approach taken by West Midlands Police that he characterises as, and I quote, 'confirmation bias'.
"This means that rather than follow the evidence, the force sought only the evidence to support their desired position to ban the fans."
She said the force failed to speak to police forces in other countries such as Greece, Ukraine and Denmark "where Maccabi Tel Aviv had played more recently and more peacefully".
Ms Mahmood called the force's communications with the Dutch police "one of the most disquieting elements" of the report.
She said: "The summary, provided as evidence to the Safety Advisory Group ahead of their crucial meeting on the 24 October, was inaccurate.
"Claims including the number of police officers deployed, links between fans and the Israeli Defence Forces, the targeting of Muslim communities, the mass tearing down of Palestinian flags, attacks on police officers and on taxi drivers were all either exaggerated or simply untrue."
Sir Andy's report also highlighted issues about poor-record keeping and mishandling of sensitive information by the force.
"He shows that the police overstated the threat posed by the Maccabi Tel Aviv fans, while understating the risk that was posed to the Israeli fans if they travelled to the area," she added.
Turning to the issue of the chief constable directly, she accused him of "misleading communications" and a "failure of leadership", saying this is why she no longer has confidence in him.
But in a letter by Sir Andy to Ms Mahmood, he wrote that he found "no evidence" of antisemitism being the reason why the police force banned fans of the team from attending the match.
What happens now?
In a statement responding to the report, West Midlands Police said it is "extremely sorry" for making mistakes and said it is taking "immediate action to address the matters raised".
But the force defended itself, saying that "none of this was done with an intent of deliberate distortion or discrimination" and that it "was always about public safety of all communities".
Meanwhile in Parliament, shadow home secretary Chris Philp said Mr Guildford "must be fired", and accused Ms Mahmood of "pretending to have no power".
Despite the findings of Sir Andy, he said: "This is a shameful episode. West Midlands police had evidence that Islamist extremists based in Birmingham planned to attack Maccabi Tel Aviv fans. Let us call that what it is: vicious antisemitism.
"We cannot allow violent Islamists to impose their will on our country, yet that is exactly what West Midlands police, through weakness and fear, allowed to happen."
But the home secretary hit back that it was the Conservatives who scrapped her ability to fire chief constables in 2011.
John Cotton, a Labour politician and leader of Birmingham City Council, has said Mr Guildford "should stand down" as "confidence needs to be restored in the leadership of West Midlands Police".
Ayoub Khan, the area's local MP who campaigned for the ban originally, has said Mr Guildford is "being thrown under a bus" and called it a "witch hunt".
The Police Federation is supportive of the government's plan to return the power to sack chief constables back to the home secretary, Sky News understands.
The body, which represents police officers in England and Wales, believes doing so could improve fairness.
Top cop apologised for providing 'erroneous' evidence
Earlier on Wednesday, CC Guildford apologised to MPs for giving them "erroneous" evidence about the decision to ban Maccabi fans, blaming the use of AI.
The police force announced in October that supporters of Maccabi Tel Aviv would not be able to attend the club's match against Aston Villa in Birmingham the following month, because it had classified the fixture as high risk based on "current intelligence and previous incidents", without saying where the threat came from.
That decision led to an outcry, with Prime Minister Sir Keir Starmer expressing concern, and senior members of West Midlands Police made to appear twice before MPs to answer questions about the ban.
The House of Commons Home Affairs Select Committee heard evidence from CC Guildford, as well as others, which led to the Board of Deputies of British Jews and the Jewish Leadership Council jointly calling for him to go.
It includes disarming Hamas, rebuilding the war-ravaged territory and establishing a group of Palestinian experts to govern Gaza under American supervision.
The National Committee for the Administration of Gaza (NCAG), which is described as a transitional technocratic body, will be responsible for administering daily affairs in Gaza.
NCAG will be overseen by the "Board of Peace", an international panel led by Donald Trump.
Phase two is outlined under a ceasefire deal, brokered by the US, which was secured after two years of war between Israel and Hamas.
"The US expects Hamas to comply fully with its obligations, including the immediate return of the final deceased hostage. Failure to do so will bring serious consequences," Witkoff wrote in a post on X.
Sky's US correspondent Mark Stone says the part about disarming Hamas is "clearly a huge challenge", and there is no detail on that.
"They [Hamas] haven't disarmed. And [Israel] also wanted the remains of the last hostage to be found and brought back... that still hasn't happened.
"Notwithstanding both of those facts, the Americans have persuaded the Israelis to agree to move to phase two.
"The other significant point is that the Palestinians also appear happy with this move to phase two. And they are endorsing it."
The mediators of the ceasefire deal - Egypt, Turkey and Qatar - welcomed the establishment of the NCAG and said it would be led by Ali Shaath, a former deputy minister in the Palestinian Authority.
Israeli Prime Minister Benjamin Netanyahu said diplomat Nickolay Mladenov, a former Bulgarian defence and foreign minister who served as UN envoy to Iraq, has been selected as the Board of Peace's director-general.
Sky's Middle East correspondent, Adam Parsons, said that "as for the second phase, it's enormously complicated. And there are so many huge assumptions within it".
"Hamas has to disarm... that is going to be a herculean task. Israel has to withdraw from the Gaza Strip. I have to say they [Israel] are not going to do that as long as Hamas has failed to disarm. These are huge boulders in the path of progress."
"This peace plan does also call for a sort of safeguarding military peacekeeping force, but there are no indications about who could serve."
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The ceasefire reached under Donald Trump's 20-point plan took effect in October and stopped much of the fighting.
But the first phase of the deal has faced multiple challenges, including Hamas failing to find and return the remains of the last remaining Israeli hostage, Israeli airstrikes which have killed hundreds of people, a refusal by Hamas to disarm and Israeli delays in reopening Gaza's Rafah border crossing with Egypt.
Although the two sides accuse each other of breaching the deal, Donald Trump says he wants to move on to the second phase.
The United Nations has estimated reconstruction will cost more than $50bn (£37bn). The process is expected to take years, and little money has been pledged so far.
Many people entered a fifth day with either no or intermittent water following the recent outages, which South East Water (SEW) blamed on Storm Goretti causing power cuts and burst pipes, resulting in the company's drinking water storage tanks running low.
SEW said on Wednesday morning that supplies had been restored to 8,000 properties across the two counties, but later said the total was 16,000.
However, it did confirm the 6,500 properties in Tunbridge Wells that had been on a "boosted system" had lost supplies for the day.
In a statement, SEW incident manager Matthew Dean said: "Water supplies have now been returned to 15,000 properties in East Grinstead and supplies should be returned to the remaining 1,500 properties tonight [Wednesday].
"The 6,500 properties in Tunbridge Wells on the boosted system lost supplies earlier today after the water levels in the area's drinking water storage tanks dropped below the level the boosters can run.
"As of 5:30pm today [Wednesday], we are implementing a new recovery plan for Tunbridge Wells which involves keeping local booster pumps switched off for a further 36 hours. Our aim is that customers wake up to a consistent water supply by Friday morning.
"Despite our best efforts, the local drinking water storage tanks have not refilled at the speed required. To resolve this, we must extend the outage to allow the storage tanks to recover fully.
"In total, around 8,000 properties across Tunbridge Wells and East Grinstead are still without water, and we are dealing with some localised issues impacting other parts of Kent."
Mr Dean added: "We are very sorry to all our customers who have been affected.
"We know and understand how difficult going without water for such a long period of time is and how difficult it makes everyday life."
SEW bosses have been recalled to appear before MPs over a separate water outage which left 24,000 properties in Tunbridge Wells without drinkable water for almost two weeks in December.
Alistair Carmichael, chairman of the Parliamentary Environment, Food and Rural Affairs committee, said he and his colleagues remained "deeply sceptical" about the company's version of events on the supply failure.
A South East Water spokesperson said: "We have fully complied with the Environment, Food and Rural Affairs Committee's request for information to date and we will continue to provide any further information requested.
"This will include attending any further meetings that are required."
Liberal Democrat leader Sir Ed Davey on Wednesday called for SEW to be stripped of its licence for "failing its customers over and over again".
Prime Minister Sir Keir Starmer, who called the situation "totally unacceptable, said ministers are holding "daily emergency meetings" about the ongoing outages.
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SEW said its customer care team is "delivering bottled water to the customers on our Priority Services Register who are most in need.
"We have completed 25,000 deliveries to customers on our register in the affected areas over the last nine days.
"We are also supporting hospitals with tankers and providing bottled water for care homes, schools, medical care providers and to support livestock."
Multiple bottled water stations continue to operate in Tunbridge Wells, East Grinstead and Maidstone, and location details can be found on SEW's website.