Low-income paying parents are more likely to build up child maintenance arrears than those who are higher paid: 46% of paying parents using the CMS did not earn enough to pay income tax (£12,570 in 2021–22), but these parents represented 62% of those with arrears as at March 2021 .Alongside making enforcement more challenging, we received written evidence from a number of non-resident parents who told us about distress and hardship they had experienced being asked for amounts they considered to be 50 C&AG’s Report, paras 21–22, 2.20 51 Q66; C&AG’s Report, para 2.20 52 Qq 70, 73–74 53 Qq 69–70; C&AG’s Report, para 2.22 54 Q 67 55 Q 32; C&AG’s Report, para 2.15 56 Q76; National Tables Child Maintenance Service Statistics data to September 2021, Table 7_2 57 Q 67 58 Qq 67 and 68; 20 Child Maintenance unreasonable, unfair or inaccurate, as well as unaffordable.59 More than two-thirds (68%) of those parents who are using Collect & Pay, and over a quarter (26%) of parents using Direct Pay, say that it is unaffordable.60