Surcharge is an additional tax levied on the amount of income-tax. This is to ensure that the contribution of taxes paid into the Consolidated fund of India by persons having a higher income, is comparitively more than the other class of taxpayers.

If you are an Individual taxpayer, then you will attract Surcharge only if your Total Income exceeds Rs.50,00,000.

Surcharge is applicable on Total Income.
Is Gross Total Income the same as Total Income?

Gross Total Income
Total Income of a taxpayer from all the heads of income is referred to as Gross Total Income.
that is, the sum total of the income of a taxpayer under five different heads of income:
- Salaries
- Income from House property
- Profits and Gains of Business or Profession
- Capital Gains
- Income from Other sources

Total Income
Total income is the income on which tax liability is determined.
It is necessary to compute Total Income to ascertain tax liability.
Chapter VI Deductions (Section 80C to 80U) provides certain deductions which can be claimed from Gross Total Income (GTI).
Total income is that portion of the income left after claiming these deductions from GTI.
In other words,
GTI less Deductions (u/s 80C to 80U) = Total Income (TI).
Note: Surcharge is calculated on Total Income before adding Health and Education Cess