The bus fare is free if you have a pre-booked ticket to Perlan. The bus has 19 seats.
You can buy an Observation Deck ticket on the bus for ISK 990. It includes:

→ Access to the 360° Observation Deck
→ A discount of ISK 990 on any exhibition ticket at Perlan
→ Bus fare on the day of your visit (both ways)

The shuttle bus departs from three locations,
Harpa at bus stop nr. 5, Hótel Natura and Perlan.

Harpa                  Hótel Natura               Perlan
10:00 am               10:15 am              10:30 am > to Harpa
11:00 am                11:15 am               11:30 am
12:00 pm                     -                        12:45 pm
01:00 pm               01:15 pm               01:30 pm
02:00 pm               02:15 pm               02:30 pm
03:00 pm               03:15 pm               03:30 pm
04:00 pm               04:15 pm               04:30 pm
05:00 pm               05:15 pm                05:30 pm
06:00 pm > to Perlan, last stop