Wastewater of baths after an exhaust dyeing of cotton knitted fabric with reactive dyestuffs, soaping and rinsing was investigated. It was found that the wastewater of rinsing baths after dyeing in a light shade, which had a small amount of dyes and electrolytes, could be used for dyeing or rinsing after dyeing in a dark shade. The dyes present in the wastewater can be removed by treatment with cross‐linked cationic starch (CCS) with a degree of substitution of about 0,3. In all cases

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... must be filtered before reuse. Such a wastewater was used for dyeing of cotton knitted fabrics in a dark shade with a laboratory apparatus. It was found that the use of wastewater in the dyeing process was risky because in some cases the colour of coloured products did not satisfy colour standards. Filtered wastewater as well as that treated with CCS were used for rinsing after dyeing of cotton and viscose knitted fabrics in a dark shade with reactive dyestuffs in industrial‐scale experiments. The colour of dyed textiles satisfied colour standards, and the colour fastness to rubbing was good.