How can I change the table names when using ASP.NET Identity?

Just for documentation purpose, for the one who comes to this post on the years anyears on the future, (like me XD), All answers given up my comment are right, but you can simplyfied with this method given by Alexandru Bucur on his blog

         //But this method is not longer supported on netcore > 2.2, so I need to fix it
         foreach (var entityType in modelBuilder.Model.GetEntityTypes())
         {
            var table = entityType.Relational().TableName;
             if (table.StartsWith("AspNet"))
             {
                 entityType.Relational().TableName = table.Substring(6);
             }
         };

        //This is the functional way on NetCore > 2.2
        foreach (var entityType in modelBuilder.Model.GetEntityTypes())
        {
            var tableName = entityType.GetTableName();
            if (tableName.StartsWith("AspNet"))
            {
                entityType.SetTableName(tableName.Substring(6));
            }
        }

You can try overriding this method in your DbContext class to map it to a table of your choosing:

    protected override void OnModelCreating(DbModelBuilder modelBuilder) {
        modelBuilder.Entity<IdentityUser>()
            .ToTable("AspNetUsers");

Below is my working solution:

public class ApplicationDbContext : IdentityDbContext<ApplicationUser>
{
    public ApplicationDbContext()
        : base("DefaultConnection", throwIfV1Schema: false)
    {
    }

    protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
        base.OnModelCreating(modelBuilder); // This needs to go before the other rules!

        modelBuilder.Entity<ApplicationUser>().ToTable("User");
        modelBuilder.Entity<IdentityRole>().ToTable("Role");
        modelBuilder.Entity<IdentityUserRole>().ToTable("UserRole");
        modelBuilder.Entity<IdentityUserClaim>().ToTable("UserClaim");
        modelBuilder.Entity<IdentityUserLogin>().ToTable("UserLogin");
    }

    public static ApplicationDbContext Create()
    {
        return new ApplicationDbContext();
    }
}

See this for more detail

You can do this easily by modifying the IdentityModel.cs as per the below:

Override OnModelCreating in your DbContext then add the following, this will change AspNetUser table to "Users" you can also change the field names the default Id column will become User_Id.

modelBuilder.Entity<IdentityUser>()
                    .ToTable("Users", "dbo").Property(p => p.Id).HasColumnName("User_Id");

or simply the below if you want to keep all the standard column names:

modelBuilder.Entity<IdentityUser>()
                        .ToTable("Users", "dbo")

Full example below (this should be in your IdentityModel.cs file) i changed my ApplicationUser class to be called User.

public class User : IdentityUser
    {
        public string PasswordOld { get; set; }
        public DateTime DateCreated { get; set; }

        public bool Activated { get; set; }

        public bool UserRole { get; set; }

    }

public class ApplicationDbContext : IdentityDbContext<User>
    {
        public ApplicationDbContext()
            : base("DefaultConnection")
        {
        }

        protected override void OnModelCreating(System.Data.Entity.DbModelBuilder modelBuilder)
        {
            base.OnModelCreating(modelBuilder);
            modelBuilder.Entity<IdentityUser>()
                .ToTable("Users", "dbo").Property(p => p.Id).HasColumnName("User_Id");
            modelBuilder.Entity<User>()
                .ToTable("Users", "dbo").Property(p => p.Id).HasColumnName("User_Id");
        }
    }

Please note i have not managed to get this working if the current table exists. Also note whatever columns you do not map the default ones will be created.

Hope that helps.