Does a person have to make up for the prayers he performed with Tayammum (dry ablution) when it was an obligation on him to perform Ghusl (ritual bath) as he was not able to perform Ghusl except after a period of time and he used to perform Tayammum instead of Ghusl?

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger. We ask Allaah to exalt his mention as well as that of his family and all his companions.

If this person had a sound reason for not performing Ghusl (ritual bath) and performed the prayer with Tayammum (dry ablution), then the answer for this is already discussed in Fatwa 82337, that he is not obliged to make up for the prayers he performed with Tayammum. However, if he did not have a sound reason, like being shy or feeling slightly cold, then he is obliged to repent to Allaah and make up for the prayers he performed with Tayammum.

Allaah Knows best.