Dean Lowe, 32, is accused of killing Kirsty Noden, also 32, who has not been seen by neighbours in Marazion, Cornwall, since January.
Officers began investigating her disappearance last week after hearing from police in a different part of the country that she may have come to harm.
Mr Lowe will appear before magistrates in Cornwall on Monday.
Miss Noden, who is also known as Kirby Noden, has links to Torquay, Ellesmere Port, Crewe and Merseyside.
A Devon and Cornwall Police spokesman said: "Miss Noden had initially been treated as a high-risk missing person following concerns for her welfare from her friends and relatives in the north west of England.
"Detectives are keen to speak to anyone who has had contact with or seen Kirsty since December 2016.
"Kirsty has yet to be located and searches and inquiries continue to trace her."
She is described as white, of heavy build and 5ft 8ins (172cm) tall.
A man has been charged with the murder of his partner, who has been missing for several months.