In QGIS 3.20 I have clusters of overlapping polygons as shown in the image below:

Clusters of overlapping polygons

My requirement is to dissolve each of these clusters into single polygons. While the "Dissolve" tool provides me with the required visual output as shown below, it ends up merging all the polygons (of all the clusters) together into a single feature.

Result when 'Dissolve' is used

The polygons in each cluster don't share a common attribute so I can't dissolve by attribute either. The full set is also too large in number for me to select them manually.

How do I dissolve based on whether or not the polygons overlap with each other?

  • 1. Dissolve, 2. Multipart to single parts
    – Babel
    May 13 at 9:10

1 Answer 1


Let's assume there are nine features in the 'grid_test' (reddish) layer, see the image below.


Use the the GDAL's "Dissolve" (GDAL > Vector geoprocessing > Dissolve) from the Processing Toolbox (Ctrl+Alt+T).

Tick the 'Produce one feature for each geometry in any kind of geometry collection in the second source' in Advance Parameters.


Press Run and get the output like this:



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