Integrated Financial Management informtion Systems as a system is globally considered as a con¬tributing factor significantly towards the improvement of financial management in the broader government sectors, it has such an important role in the world and particularly in Kenya as a coun¬try. The expectation is that the usage of IFMIS makes public finances comprehensive and effec¬tive. All the same, the system has not been addressed in full, its operations and performance is strongly wanting. This study sought to establish ; Extended Acceptance and Use of Information Technology Model: Assessing Integrated Financial Management information Systems in the Pub¬lic Sector. This study utilized: UTAUT theory; DeLone and McLean model as tools to test IFMIS. Objectives were to: establish the Capacity of IT Infrastructure, examine the effect of technical op¬eration skills, assess management skills and develope a model. Data was collected by question¬naires. The research design was descriptive survey; a Sample size of 300, with a target of 1200 employees in the public sector. Validity, reliability and pilot study was done, Where (p < = 0.05, alpha <0.7; KMO <0.5) were levels used. Second generation techniques (SEM) were employed with methods: Nested comparison, Bootstrapping, Impulsive Decision Scale, Multiple group model comparison, Latent growth curve and Split path model comparison. Model fit > 0.90, RMR <O. 02,RMSEA = < 0.05. Finding indicates :COITI had a higher error difference. Delone & Mclean model split path diagrams had lower error difference. D & M model yielded results ratio (1.5906) less than 2 hence good fit. External Model posted (CFI = 0.91 hence> 0.9: MgtS posted NF!= 0.98, GFI = 0.99 > 0.9 signifying a good fit (rule of thumb) for the use ofIFMIS. Overall model results indicated (RMR = 0.010 and RMSEA = 0.027) all above the threshold respectively. Effects of TOS and MgtS models were satisfactory. Results confirm that D & Mand External Model indi¬cated Good fit , both contributed to the use of IFMIS more than UTA UT model. Finding also indi¬cates that counties had slightly lower effective management skills and Technical operation skills. On overall, COITI registered a low significance, weak effect (Factor loading-low) and high error difference (10% ). Conclusion: Counties, Ministry-C , and Public universities ; indicated a low achievement on COITI-low contribution to the use of IFMIS ; TOS performed well at Public uni¬versities , Ministry-C and Parastatals as opposed to counties. Study Contributions were : employed six unique techniques , contributed five new constructs and developed SMAUIT model. Recom¬mends to the public sector were : Re-equipment of IT Infrastructure, setting up security compo¬nents per each sector ( DMZs) to curb system Hacking in all Government sectors.