How would reply to igualmente?

The most common and direct reply to "igualmente" is "igualmente". It's a polite way of saying "you too" or "likewise" in Spanish.

Here are some other options, depending on the context:

Formal:

* De igual manera. (Similarly)

* Recíprocamente. (Reciprocally)

* Con el mismo gusto. (With pleasure)

Informal:

* Lo mismo. (The same)

* Igual. (Same)

* Tú también. (You too)

* Gracias. (Thank you)

Example:

* Person A: ¡Que tengas un buen día! (Have a good day!)

* Person B: ¡Igualmente! (You too!)