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Intro: Extensively drug-resistant (XDR) Salmonella Typhi has been reported in Sindh province of Pakistan since 2016. The potential for further spread is of serious concern as remaining treatment options are severely limited. We report the phenotypic and genotypic characterization of 27 XDR S. Typhi isolated from patients attending Jinnah Hospital, Lahore, Pakistan. Positive Blood Cultures for Salmonella Typhi raised the possibility that the Sindh province strain was circulating in Lahore, leading us to sequence 27 XDR S. Typhi isolates and compare SNPs in their whole genome sequences with those from Sindh. Methods: Isolates were identified by biochemical profiling; antimicrobial susceptibility was determined by a modified Kirby–Bauer method. These findings were confirmed using Illumina whole genome nucleotide sequence data. All sequences were compared to the outbreak strain from Southern Pakistan and typed using the S. Typhi genotyping scheme. All isolates were confirmed by sequence analysis to harbor an IncY plasmid and the CTX-M-15 ceftriaxone resistance determinant. All isolates were of the same genotypic background as the outbreak strain from Sindh province. Findings: All the XDR isolates differed by six SNPs from the MDR S. Typhi clade, the same level of variation as seen during the 2016 outbreak. Within the XDR clade, the Lahore isolates formed two clusters on the tree, one consisting of isolates XDR1, 21, 5, 28, and 27, and the other of XDR24, 4, 17, 6, 13, 10, 23, 19, 30, 26, 25, 15, 22, 35, 31, and 2, suggesting probable epidemiological linkage. Analysis of all 27 draft genome sequences from Lahore indicated the presence of both an IncY plasmid and the CTX-M-15 determinant associated with ceftriaxone resistance. Conclusion: In conclusion, the risk of single point mutations conferring resistance to azithromycin and of the horizontal transmission of carbapenemase-mediated resistance makes the ongoing threat of XDR typhoid fever very real in Pakistan and internationally.