Q2 F2023 - Bank of the West Contribution & Financial Results

Performing Loans (PCL) By Operating Group ($MM) Personal & Business Banking 877 43 0 920 Commercial Banking 396 12 3 411 Total Canadian P&C 1,273 55 3 1,331 Personal & Business Banking 178 6 233 417 Commercial Banking 714 (3) 470 1,181 Total U.S. P&C 892 3 703 1,598 Allowance and Provision on Performing Loans Allowance on Performing Loans (APL) and PCL on Q1 23 APL¹ Q2 23 Q2 23 Foreign Q2 23 PCL² exchange APL¹ & Other APL to Performing Loans (bps)³ • The $780MM reported provision for performing loans includes: - - $705MM charge for the initial allowance on the BOTW purchased performing portfolio On an adjusted basis, the $75 million provision for credit losses on performing loans in the current quarter reflected portfolio credit migration, model changes and economic uncertainty, partially offset by a modest improvement in macro-economic variables, including the continued benefit from risk transfer transactions Allowance on Performing Loans Ratio (bps) 45 38 42 84 71 74 BMO Wealth Management 33 3 0 36 8 51 44 43 45 44 BMO Capital Markets 307 17 9 333 43 Corporate Services 702 (694) 14 n.m. Q2'22 Q3'22 Q4'22 Q1'23 Q2'23 Total BMO - Reported 2,511 780 21 3,312 51 - BOTW Initial Allowance4 (705) --Allowance on Performing Loans Ratio (bps)³ Coverage Ratio Total BMO - Adjusted 6 75 6.35 5.90 4.90 4.10 4.25 1 Q1 23 and Q2 23 includes APL on Other Assets of $21MM and $22MM, respectively and excludes APL on Securities of $3MM and $6MM, respectively Q2'22 2 Q2 23 PCL includes a PCL on Other Assets of $2MM and excludes PCL on Securities of $2MM 3 Allowance on performing loans over total gross performing loan and acceptances, expressed in basis points 4 Initial allowance for BOTW is as of February 1, 2023 5 Trailing 4-Quarter PCL on impaired loans includes Q2 23 annualized BOTW PCL 6 Adjusted results and measures are non-GAAP, see slide 40 for more information and slide 41 for adjustments to reported results BMOM Q4'22 Q1'23 Q3'22 Q2'235 Allowance on performing loans over trailing 4-quarter PCL on impaired loans • Risk Review May 24, 2023 26

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