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Keetels, a member of the victorious 2014 World Cup team, fired low past Maddie Hinch in the fourth quarter after two shots had been blocked.
England won several penalty corners, but were frustrated by a resilient Dutch defence.
Alex Danson did go close though with a shot saved by keeper Anne Veenendaal.
Danson's team-mate Sophie Bray also went agonisingly close to scoring as she failed to convert Zoe Shipperley' low driven pass.
Keetels said: "It was amazing. I'm so happy. The English attacked and defended well.
"We are enjoying the pressure. The crowd is all orange so it feels like an extra player on the field."
The home nation will play neighbours Belgium in Saturday's final. England will take on Germany for the bronze medal prior to that match.
England play Netherlands again, this time in the men's semi-finals on Friday (19:00 BST).
England's hopes of defending their EuroHockey title were thwarted at the semi-final stage as Marloes Keetels' strike sent hosts Netherlands through.