‹ PRU 3.9 Tier 1 capital Guidance › PRU 3.9.1 Tier 1 capital must be calculated as the total of its Common Equity Tier 1 capital (referred to in these Rules as CET1 Capital) and its Additional Tier 1 capital (referred to in these Rules as AT1 Capital). ‹ PRU 3.9 Tier 1 capital Guidance ›