The information in this preliminary pricing supplement is not complete and may be changed. Preliminary Pricing SupplementSubject to Completion: Dated June 17, 2026 Auto-Callable Contingent Coupon Barrier NotesLinked to the Least Performing of Two Underliers,Due June 28, 2029 Pricing Supplement dated June __, 2026 to the Prospectusdated December 20, 2023, the Prospectus Supplementdated December 20, 2023, the Underlying Supplement No.1A dated May 16, 2024 and the Product Supplement No. Royal Bank of Canada Royal Bank of Canada is offering Auto-Callable Contingent Coupon Barrier Notes (the “Notes”) linked to the performanceof the least performing of the Russell 2000®Index and the S&P 500® Index (each, an “Underlier”).Contingent Coupons— If the Notes have not been automatically called, investors will receive a Contingent Coupon on a quarterly Coupon Payment Date at a rate of 8.10% per annum if the closing value of each Underlieris greater than or equal to its Coupon Threshold (70% of its Initial Underlier Value) on the immediately precedingCoupon Observation Date. You may not receive any Contingent Coupons during the term of the Notes. Call Feature— If, on any quarterly Call Observation Date beginning approximately one year following the TradeDate, the closing value of each Underlier is greater than or equal to its Initial Underlier Value, the Notes will beautomatically called for 100% of their principal amountplusthe Contingent Coupon otherwise due. No furtherpayments will be made on the Notes. Contingent Return of Principal at Maturity— If the Notes are not automatically called and the Final UnderlierValue of the Least Performing Underlier is greater than or equal to its Barrier Value (70% of its Initial UnderlierValue), at maturity, investors will receive the principal amount of their Notesplusthe Contingent Coupon otherwisedue. If the Notes are not automatically called and the Final Underlier Value of the Least Performing Underlier is Any payments on the Notes are subject to our credit risk.The Notes will not be listed on any securities exchange. CUSIP:78017UD23 Investing in the Notes involves a number of risks. See “Selected Risk Considerations” beginning on page P-7 of this pricing supplement and “Risk Factors” in the accompanying prospectus, prospectus supplement andproduct supplement. None of the Securities and Exchange Commission (the “SEC”), any state securities commission or any other regulatorybody has approved or disapproved of the Notes or passed upon the adequacy or accuracy of this pricing supplement. Anyrepresentation to the contrary is a criminal offense. The Notes will not constitute deposits insured by the Canada DepositInsurance Corporation, the U.S. Federal Deposit Insurance Corporation or any other Canadian or U.S. governmentalagency or instrumentality. The Notes are not bail-inable notes and are not subject to conversion into our common shares We or one of our affiliates may pay varying selling concessions of up to $23.50 per $1,000 principal amount of Notes inconnection with the distribution of the Notes to other registered broker-dealers. Certain dealers who purchase the Notesfor sale to certain fee-based advisory accounts may forgo some or all of their underwriting discount or selling concessions.The public offering price for investors purchasing the Notes in these accounts may be between $976.50 and $1,000.00 per$1,000 principal amount of Notes. See “Supplemental Plan of Distribution (Conflicts of Interest)” below. The initial estimated value of the Notes determined by us as of the Trade Date, which we refer to as the initial estimatedvalue, is expected to be between $900.00 and $950.00 per $1,000 principal amount of Notes and will be less than thepublic offering price of the Notes. The final pricing supplement relating to the Notes will set forth the initial estimated value.The market value of the Notes at any time will reflect many factors, cannot be predicted with accuracy and may be less KEY TERMS The information in this “Key Terms” section is qualified by any more detailed information set forth in this pricingsupplementand in the accompanying prospectus,prospectus supplement,underlying supplement and productsupplement. Royal Bank of CanadaRBC Capital Markets, LLC (“RBCCM”) $1,000 and minimum denominations of $1,000 in excess thereof The Russell 2000®Index (the “RTY Index”) and the S&P 500® Trade Date:Issue Date:Valuation Date:*Maturity Date:*Payment of ContingentCoupons: If the Notes have not been automatically called, investors will receive a ContingentCoupon on a Coupon Payment Date if the closing value of each Underlier isgreaterthanor equal to its Coupon Threshold on the immediately preceding Coupon No Contingent Coupon will be payable on a Coupon Payment Date if the closing value ofany Underlier is less than its Coupon Threshold on the immediately preceding CouponObservation Date. Accordingly, you may not receive a Contingent Coupon on one ormore