Mortgage underwriters normally want documentation attached to the letter of explanation. For example, a letter of explanation may be required if a mortgage loan borrower had a substantial low income one year from the previous year and had a late payment history for three months.
Wage garnishment by itself will not damage your credit...and the fact that your wages are being garnishment will not be noted on your credit report....However, the judgment that led to the garnishment (if they report it) will affect your credit rating...and the original default of your credit card will also still damage your credit rating.
Creditors can also calculate your garnishment based on your disposable income. The law allows creditors to choose the lesser of 15 percent of your gross wages or any disposable income that exceeds 45 times the Illinois minimum wage, which is $8.25 an hour at the time of publication.