The window costs in this article are correct as of 2019
If you have a window that’s smashed or otherwise broken, you’ll want to replace it as quickly as possible.
If a single pane, or multiple panes of glass are broken, you may be able to replace them individually, depending on the style of the window unit and how it is constructed. The material costs for replacing a pane of glass is not particularly expensive, however, a window fitter or glazier will charge for their time and for being called out. A simple pane of non-double-glazed glass, say in a patio door, may cost as little as £100 to replace. However, replacing a double-glazed pane can be much more difficult as the whole unit comes as a single piece. At that point, a good window fitter can tell you if you need to replace the whole window.
If replacing a whole window, the cost will depend on the size and style of the window. A small, double-glazed casement window, such as the one you might find in a bathroom or utility room, can cost as little as £200 to replace, while larger windows like in living rooms or bedrooms can rise to £400 to £600. If you are looking for wooden-framed windows, rather than uPVC, the cost will be greater, usually at least double the price, and the prices can escalate massively if you are using less common woods - individual windows can then cost thousands of pounds.
As with most home improvement projects, it is worth speaking to more than one tradesperson and getting a range of quotes to compare prices. A locksmith may be able to seal up a broken window temporarily, but a glazier or window fitter will be best placed to install a new window.