The jets are made by British firm BAE Systems, as part of a multi-billion pound deal which has been under discussion for many years.
The BAE System said in a statement that the signing is a positive step ahead in direction of friendly relations.
The memorandum of intent was signed after Saudi Crown Prince Mohammed bin Salman met with British defence minister Gavin Williamson.
BAE Systems delivered the last of 72 Eurofighter in June 2017, which included 48 single seat and 24 twin seat variants.
Mrs May defended the UK's ties with Saudi Arabia earlier this week, saying all arms sales are strictly regulated.
During the hour-long visit at Lambeth Palace, the pair discussed the crown prince's reform plans and Welby - the head of the Anglican church - expressed his concerns about the treatment of Christians in Saudi Arabia.
The British government is defending the sale of the planes to Saudi Arabia amid growing pressure to completely halt arms exports to Saudi Arabia with critics warning it will strengthen Riyadh's hand in its ongoing military campaign in Yemen.
The thorny topic of Yemen was on the agenda at a private dinner at May's country residence on Thursday night, but it was tempered with gifts: May's office said she presented Prince Mohammed with a family tree showing the descent of the Al Saud dynasty.
In the lead-up to the trip, tens of thousands of Britons had signed online petitions calling on Theresa May, the prime minister, to cancel MBS' visit over his actions towards his southern neighbour.
Andrew Smith of Campaign Against Arms Trade said the United Kingdom had already licensed £4.6bn of arms for Saudi Arabia since the Yemen conflict began in 2015.
Prior to his trip to the United Kingdom, the Crown Prince had traveled to Egypt on a three-day visit.
The Eurofighter Typhoon is the most advanced swing-role combat aircraft available and there are nearly 500 in service across Europe.
- Daylight Saving Time Kicks In This Sunday At 2a
- Russians involved in USA election interference possibly Jews: Putin
- Tesla CEO Elon Musk weighs in on Trump trade battle with China
- India's top court upholds passive euthanasia with guidelines: chief justice
- Russian Federation expert analyzes spy poisoning case in UK
- France have beaten England - Ireland are the 2018 Six Nations champions
- Border Patrol Defends Actions After Video of Mother's Arrest Sparks Public Outrage
- Florida governor signs gun restrictions three weeks after attack
- West Ham boss Moyes confirms Hart recall
- Waffle House worker captured in act of kindness