Research carried out by Which? suggests taxpayers who need to speak to HMRC for help or advice ahead of the self-assessment tax return deadline could face a lengthy wait. The consumer group made 100 calls to HMRC's self-assessment and general enquiries helplines and found that, on average, it took 38 minutes to speak to a real person, with nearly one in five of its calls not answered within an hour. The longest wait was one hour and 16 minutes.