Can you find a château wedding venue in France under €20,000?
Yes, comfortably. It depends on the region, the season, the day of the week and what the price includes — the same budget does not buy the same thing in Provence and in the Dordogne.
Regional gaps are considerable
Provence, Bordeaux, the Dordogne, the Loire Valley: for comparable properties, listed prices vary threefold. Widening the search to two or three regions is usually more effective than negotiating hard in one.
Availability, the forgotten lever
A date that stays open creates an opportunity for the couple and for the venue. Saturdays from June to September are the most contested; a Friday, a Sunday, or a date in April or October changes the price level entirely.
Compare like with like
A price means nothing without its duration, its beds and its catering terms. A €12,000 venue over three days sleeping forty can cost less in the end than a €9,000 single day.
See also: real prices by region · venues under €5,000