The Department has no long-term strategy for tackling the growing unpaid maintenance balance under the current CMS scheme. Unpaid maintenance owed to parents on Collect & Pay has increased by more than £1 million per week to a total of £440 million as at October 2021.66 We therefore asked the Department how it planned to address the increasing arrears balance within the scheme. The Department told us that “a lot of it is already in payment” and it is “not giving up on getting all of it”.67 However, the NAO reported that no payment was made against around four-fifths (79%) of this debt in September 2021. It concluded that, unless the Department writes off more of the debt, outstanding arrears will grow to £1 billion by March 2031 at current rates, and indefinitely 59 Written evidence CMS0007, anonymised; Written Evidence CMS0040, anonymised; Written evidence CMS 0030, anonymised 60 C&AG’s Report, para 23.2.23 61 Q 79 62 Q 79 63 Q 80, 82; C&AG’s Report, para 2.3, 2.24 64 C&AG’s Report, paras 15, 1.16 65 CMS 0042 66 C&AG’s Report, paras 25, 2.29 67 Qq 85–86 and 88 Child Maintenance 21 thereafter.68 The Department told us it expected investment in transforming its services to give it 15% more capacity to focus on compliance. However, even if compliance rates improve the Department will only delay the date the level of unpaid maintenance reaches £1 billion to 2033–34.69 The Department also told us that it expected only a minority of debt to fall into a category it described as “at the moment, we can’t see how the parent can pay and we’re just keeping a watching brief.” However, the Department does not currently have legal authority to write off uncollectable CMS arrears and has yet to decide how to treat cases which it has identified where the money owed is ‘potentially uncollectable’ because it has exhausted its enforcement options.70 Fraud and error in maintenance payments