Boddy, 19, made 11 appearances for Barclays Women's Championship winners Bristol City Women last season.
Prior to the 2022/23 campaign, the midfielder had a six-month stint in the Women's Super League (WSL) with Leicester City Women, where she made her WSL debut aged just 18.
Boddy began her career at Middlesbrough, making her senior debut with the Teesside club at the age of 16.
Despite her age, the midfielder has bundles of experience in the top three tiers of women's football and still has her best years ahead of her.
Boddy has also represented England from under-15s to under-19s level, scoring against Finland on her under-19s debut in February 2022.
Newcastle Women manager Becky Langley is thrilled to have secured Boddy's signature, stating: "From our first conversation, I knew Elysia was perfectly suited for Newcastle United.
"She's very focused, very professional and driven to take this club to the WSL.
"We instantly clicked, so I'm excited to work with Elysia."
See Elysia Boddy in action when Newcastle United Women play West Bromwich Albion Women at St. James' Park on Saturday, 5th August as part of the two-day Sela Cup, presented by VisitMalta. Buy tickets here.