In this situation, do you have to signal your intention to return to the right lane with a right turn signal?

In the video, after overtaking a red car, you are driving in the left lane of a dual carriageway outside town; the right lane is free. When you intend to return to the right lane, you are obliged to signal this intention with your right indicator. The answer is: yes.

The Road Traffic Act requires the driver to signal in good time and clearly the intention to change direction or lane, and to stop signalling immediately after completing the manoeuvre; when changing lanes, the driver must also give way to a vehicle travelling in the lane they intend to move into. Returning to the right lane after overtaking is a lane change like any other, so the indicator is required - the right one, because that is the side you are moving to. Many drivers skip it, thinking that the return "goes without saying", but the driver behind you in the left lane and the one who is just entering the right lane from a slip road must know what you intend to do. The order is always the same: mirror, indicator, mirror again and blind spot, a smooth move into the right lane, indicator off. The Act also requires you to drive as close as possible to the right-hand edge, so you do not stay in the left lane longer than overtaking requires.

Legal basis: Art. 22 para. 4 and 5 and Art. 16 para. 4 of the Road Traffic Act (Prawo o ruchu drogowym)