She revealed the news to councillors attending the latest round of committee meetings in the Angel Suite.
There were some stunned looks - not least on the Press bench!
Jeanette will remain in post for three months while a successor is appointed.
Her decision to retire forms an agenda item at March's Town Council meeting, to be held next Monday night in the Angel Suite (full agenda to follow tomorrow on Brigg Blog).
Various administrative procedures will be required as the recruitment process begins.
There will be tributes to Jeanette's hard work and efficiency over the coming weeks, culminating in her final meeting as Town Clerk, in June. We will be adding our own, in due course.
The phrase "He/she will be a very hard act to follow" is often used when people retire, but in Jeanette's case this is most certainly the case.
She wishes to spend much more time with her family.
We have been reporting on Town Council meetings since January 1980, when veteran Joseph J Magrath was the Clerk. We continued to do so during the tenure of Louis T Jarratt who, like Jeanette, came to us from Scawby.
Experience and local knowledge are two factors you don't often see in job specifications but they are of great benefit to the officers who oversee the administration of parish and town councils.