HM Revenue and Customs (HMRC) has detailed 10 legitimate reasons that could save you from a £100 penalty for missing the self-assessment deadline. A reasonable excuse is defined as an unforeseen circumstance that prevented you from fulfilling a tax obligation, despite taking reasonable care to do so.

Examples provided by HMRC include the death of a partner or close relative shortly before the tax return or payment deadline, an unexpected hospital stay that hindered you from managing your tax affairs, and serious or life-threatening illnesses. Technical issues such as computer or software failure while preparing your online return, or service disruptions with HMRC’s online services, are also considered valid excuses.

Other acceptable reasons include a fire, flood or theft that prevented you from completing your tax return, unpredictable postal delays, delays due to a disability or mental illness, and misunderstanding or lack of awareness about your legal obligation. If you relied on someone else to submit your return and they failed to do so, this is also considered a valid excuse.

View of a young man, sitting in his living room at home next to his laptop, with worried expression while checking home bills. Concept of home economics.
According to HM Revenue and Customs (HMRC), an estimated 1.1 million people missed the deadline for filing their annual tax returns. (Image: Getty)

According to HMRC, an estimated 1.1 million people missed the deadline for filing their annual tax returns. Those who missed the self-assessment deadline last Friday are now facing a minimum fine of £100, as per the tax authority’s rules. However, this penalty can be avoided if they have a valid reason for their delay, reports Devon Live.

HMRC has disclosed that more than 11.5 million people filed their self-assessment by the deadline, with an impressive last-minute dash of 31,000 submissions in the final hour, reports Birmingham Live. Filing is obligatory for the self-employed and those with various income sources.

Meanwhile, HMRC has flatly denied allegations put forward by MPs suggesting they keep a “deliberately poor” call centre service to drive people online. HMRC’s chief executive, Jim Harra, labelled these claims as “completely baseless”.