20a. Non-current receivabeles

in PLN thousand	As at 31 December 2018	As at 31 December 2017
Receivables due from finance lease	6 376	6 819
Receivables due from sale of tangible fixed assets	1 256	1 910
Advances for construction in progress	2 093	-
	9 725	8 729

20b. Trade and other receivables

in PLN thousand	As at 31 December 2018	As at 31 December 2017 (transformed data)
Trade receivables due from related parties	32 027	33 778
Trade receivables due from other entities	63 535	61 490
Tax and social security receivables	-	2 752
Receivables due from sale of tangible fixed assets	718	718
Prepayments and deferred costs in respect of the program of connecting buildings to the heat distribution network	1 618	1 718
Prepayments and deferred costs in respect of property and civil liability insurance	2 975	2 911
Finance leases receivables	438	446
Other receivables	97	253
	101 408	104 066

in PLN thousand	As at 31 December 2018	As at 31 December 2017
Gross overdue receivables
up to 1 month	1 669	810
over 1 month up to 3 months	15	38
over 3 months up to 6 months	1	4
over 6 months up to 1 year	15	10
over 1 year	536	421
	2 236	1 283
Bad debt allowances for overdue receivables	(1 687)	(438)
Net overdue receivables	549	845