Just right for Labour Day in Corona times: As of June 30, 2019, 11,129 Czech citizens were employed in Saxony subject to social security contributions. In addition, there were 986 marginally employed persons who are not included in the following evaluations.
Most of these employees, namely 9,134, are cross-border commuters, i.e. they lived in the Czech Republic. This share of 82% commuters is much higher than, for example, for Polish employees in Saxony (53%).
If you look at the sectors, it is not - as one might expect - the hotel and restaurant industry or the health care sector that are in first place, but the manufacturing industry, which employs almost a quarter of the Czech workforce.
In Euroregion Elbe/Labe, 3,307 Czech citizens worked on the German side, of which 2,629 are cross-border commuters. In addition, 350 Czech* nationals were marginally employed here.
In the whole of Germany, approx. 35,700 cross-border commuters from the Czech Republic are employed (in Bavaria there are probably more than 25,000). This shows the extent of the effects of the current border closures.
More interesting information (also on Polish employees in Saxony) can be found in the DGB's short info of 28.04.2020 (PDF, German only).