Question: I am stuck with placing Label on the Grid lines. Below is the data grid on the map. I created the grid using data driven pages.
After I turned on the Label, the labelling appeared inside the grid. I want it to be placed on the line itself with a little buffer around it. I have explored the placement properties of the grid layer and it looks as if there is no option there[![Current Grid](https://i.stack.imgur.com/f0B6B.jpg)](https://i.stack.imgur.com/f0B6B.jpg)

I wish I could placed the Labeling on the gridLines/borders instead of inside the grid.

Answer: 
The ["Polygonize"](https://docs.qgis.org/3.16/en/docs/user_manual/processing_algs/qgis/vectorgeometry.html#polygonize) tool from the Processing toolbox still works fine for me on simple lines:

[![enter image description here](https://i.stack.imgur.com/nQzi9.png)](https://i.stack.imgur.com/nQzi9.png)

It is however necessary that the lines intersect, or share common vertices. And lines should have no self-intersection.

You might need to snap the corner vertices to get it working. I usually set the snapping tolerance to 10 pixels to the vertex.
Just a hint if you can't find the `Polygonize` tool. In my QGIS 2.18.3 installation (Windows) I could not find the `Polygonize` tool at `Vector geometry tools` within the Toolbox. It took me some time to realize that I needed to install the `python-shapely` library with OSGeo4W (thanks [Nick Hopton : Perfect Polygons in QGIS](http://confound.me.uk/maps/ppv4.pdf)).