Harry, the Duke of Sussex, also wore his No 1 RAF uniform, with RAF Regiment shoulder flashes, in recognition of Honington - the home of the RAF Regiment - and also for his role as Honorary Air Commandant of the base.
Fittingly, Meghan Markle arrived wearing a forest green pencil dress by Givenchy which featured pocket detailing, while holding a tan leather tote.
"Navy looks very smart and in it she can't go wrong".
It's a busy day for the former actress, who will be heading off to Ireland with her husband later in the day for an official two-day visit - their first overseas! I like that she's still given such a classic look a contemporary twist, by wearing the bun to the side, rather than in the middle of her head.
As well as being Britain's top defense system in air, the RAF has prevented conflicts and delivered aid in areas hit by natural disasters over the last many decades.
Kate Middleton and Meghan Markle joined the princes for a service at Westminster Abbey. Meetings with The President of Ireland, Michael Higgins, and with The Taoiseach, Leo Varadkar, are both planned.
The Duke and Duchess will also visit DogPatch Labs, a co-working space for technology start-ups, where they will meet children and young people taking part in workshops, and talk to female tech entrepreneurs.