اَللّهُمَّ إِنَّ هذَا بَدَنُ عَبْدِكَ الْمُؤْمِنِ، قَدْ أَخْرَجْتَ رُوْحَهُ مِنْهُ، وَفَرَّقْتَ بَيْنَهُمَا، فَعَفْوَكَ عَفْوَكَ.

AL-LAAHUM-MA IN-NA HAADHAA BADANU 'ABDIKAL MU'MIN WA QAD AKHRAJTA ROOHAHU MINHOO WA FARAQTA BAYNAHUMAA FA'AFWAKA 'AFWAK

O Allah this is the body of Your Momin whose spirit You have taken from it and have thus separated the two. So, Your forgiveness is sought, Your forgiveness is sought.

It Is Mustahab (recommended) To Recite The Following Du'a When Giving Ghusl To A Mayyit.
If the mayyit is a male, recite the following:

اَللّهُمَّ إِنَّ هذَا بَدَنُ أَمَتِكَ الْمُؤْمِنَةِ، قَدْ أَخْرَجْتَ رُوْحَها مِنْهُ، وَفَرَّقْتَ بَيْنَهُمَا، فَعَفْوَكَ عَفْوَكَ.

AL-LAAHUM-MA IN-NA HAADHAA BADANU AMATIKAL MUʼMINATI WA QAD AKHRAJTA ROOHAHAA MINHOO WA FARAQTA BAYNAHUMAA FA'AFWAKA 'AFWAK

O Allah this is the body of Your Mominah whose spirit you have taken from it and have thus separated the two. So, Your forgiveness is sought, Your forgiveness is sought.

If the mayyit is a female, recite the following