User element (UEL) subroutine (user-defined element) is the highest level of a subroutine that Abaqus offers to its users. This subroutine allows the user to program the basic building block of a finite element simulation. This subroutine becomes very powerful when the user wants to implement a type of element that is not available in Abaqus. Using this subroutine, user can define different types of shape functions, introduce element technology that is not available in Abaqus, or simulate multiphysical behavior that is not possible otherwise. This Abaqus user element tutorial package will give a brief introduction to the user element subroutine followed by theory and algorithm to write subroutine small strain mechanical analysis. First, we will highlight the UEL element stiffness matrix and element residual vector which are to be programmed in the first example. We will also cover shape functions and numerical integration. Next, we’ll talk about UEL inputs and outputs. The first example contains the detailed development procedure of a general-purpose subroutine for 2D plane-strain and 3D simulations using triangular, quadrilateral, tetrahedral, and hexahedral type of elements with reduced and full integration scheme. The second example demonstrates the procedure to build UEL-compatible model in Abaqus/CAE. It also demonstrates how to apply complicated boundary conditions with UEL as well as perform Abaqus analysis on structures which has standard and user elements. As an outcome, user can write their own UEL subroutine afterwards using this program as template.