A PO BOX number can be less than or more than four digit. For post office boxes, the general rule is that each box has its own ZIP+4 code.
The last four digit is often one of the following:
1. Zero plus the last three digits of the box number (eg. PO BOX 1001, Los Angeles CA 90001-0001).
2. The last four digits of the box number (eg. PO BOX 9991, Twin Peaks CA 92391-9991).
3. If the box number is less than four digits, enough zeros prepended to the front of the box number to produce a four-digit number(eg. PO BOX 1, Shreveport LA 71161-0001).
However, there is no uniform rule, the zip code plus four is for reference only, the ZIP+4 code must be looked up individually for each box in the USPS offical website.
PO BOX 3800, FORT SMITH, AR 72913-3800
PO BOX 3801, FORT SMITH, AR 72913-3801
PO BOX 3802, FORT SMITH, AR 72913-3802
PO BOX 3803, FORT SMITH, AR 72913-3803
PO BOX 3804, FORT SMITH, AR 72913-3804
PO BOX 3805, FORT SMITH, AR 72913-3805
PO BOX 3806, FORT SMITH, AR 72913-3806
PO BOX 3807, FORT SMITH, AR 72913-3807
PO BOX 3808, FORT SMITH, AR 72913-3808
PO BOX 3809, FORT SMITH, AR 72913-3809
PO BOX 3810, FORT SMITH, AR 72913-3810
PO BOX 3811, FORT SMITH, AR 72913-3811
PO BOX 3812, FORT SMITH, AR 72913-3812
PO BOX 3813, FORT SMITH, AR 72913-3813
PO BOX 3814, FORT SMITH, AR 72913-3814
PO BOX 3815, FORT SMITH, AR 72913-3815
PO BOX 3816, FORT SMITH, AR 72913-3816
PO BOX 3817, FORT SMITH, AR 72913-3817
PO BOX 3818, FORT SMITH, AR 72913-3818
PO BOX 3819, FORT SMITH, AR 72913-3819
PO BOX 3820, FORT SMITH, AR 72913-3820
PO BOX 3821, FORT SMITH, AR 72913-3821
PO BOX 3822, FORT SMITH, AR 72913-3822
PO BOX 3823, FORT SMITH, AR 72913-3823
PO BOX 3824, FORT SMITH, AR 72913-3824
PO BOX 3825, FORT SMITH, AR 72913-3825
PO BOX 3826, FORT SMITH, AR 72913-3826
PO BOX 3827, FORT SMITH, AR 72913-3827
PO BOX 3828, FORT SMITH, AR 72913-3828
PO BOX 3829, FORT SMITH, AR 72913-3829
PO BOX 3830, FORT SMITH, AR 72913-3830
PO BOX 3831, FORT SMITH, AR 72913-3831
PO BOX 3832, FORT SMITH, AR 72913-3832
PO BOX 3833, FORT SMITH, AR 72913-3833
PO BOX 3834, FORT SMITH, AR 72913-3834
PO BOX 3835, FORT SMITH, AR 72913-3835
PO BOX 3836, FORT SMITH, AR 72913-3836
PO BOX 3837, FORT SMITH, AR 72913-3837
PO BOX 3838, FORT SMITH, AR 72913-3838
PO BOX 3839, FORT SMITH, AR 72913-3839
PO BOX 3840, FORT SMITH, AR 72913-3840
PO BOX 3841, FORT SMITH, AR 72913-3841
PO BOX 3842, FORT SMITH, AR 72913-3842
PO BOX 3843, FORT SMITH, AR 72913-3843
PO BOX 3844, FORT SMITH, AR 72913-3844
PO BOX 3845, FORT SMITH, AR 72913-3845
PO BOX 3846, FORT SMITH, AR 72913-3846
PO BOX 3847, FORT SMITH, AR 72913-3847
PO BOX 3848, FORT SMITH, AR 72913-3848
PO BOX 3849, FORT SMITH, AR 72913-3849
PO BOX 3850, FORT SMITH, AR 72913-3850
PO BOX 3851, FORT SMITH, AR 72913-3851
PO BOX 3852, FORT SMITH, AR 72913-3852
PO BOX 3853, FORT SMITH, AR 72913-3853
PO BOX 3854, FORT SMITH, AR 72913-3854
PO BOX 3855, FORT SMITH, AR 72913-3855
PO BOX 3856, FORT SMITH, AR 72913-3856
PO BOX 3857, FORT SMITH, AR 72913-3857
PO BOX 3858, FORT SMITH, AR 72913-3858
PO BOX 3859, FORT SMITH, AR 72913-3859
PO BOX 3860, FORT SMITH, AR 72913-3860
PO BOX 3861, FORT SMITH, AR 72913-3861
PO BOX 3862, FORT SMITH, AR 72913-3862
PO BOX 3863, FORT SMITH, AR 72913-3863
PO BOX 3864, FORT SMITH, AR 72913-3864
PO BOX 3865, FORT SMITH, AR 72913-3865
PO BOX 3866, FORT SMITH, AR 72913-3866
PO BOX 3867, FORT SMITH, AR 72913-3867
PO BOX 3868, FORT SMITH, AR 72913-3868
PO BOX 3869, FORT SMITH, AR 72913-3869
PO BOX 3870, FORT SMITH, AR 72913-3870
PO BOX 3871, FORT SMITH, AR 72913-3871
PO BOX 3872, FORT SMITH, AR 72913-3872
PO BOX 3873, FORT SMITH, AR 72913-3873
PO BOX 3874, FORT SMITH, AR 72913-3874
PO BOX 3875, FORT SMITH, AR 72913-3875
PO BOX 3876, FORT SMITH, AR 72913-3876
PO BOX 3877, FORT SMITH, AR 72913-3877
PO BOX 3878, FORT SMITH, AR 72913-3878
PO BOX 3879, FORT SMITH, AR 72913-3879
PO BOX 3880, FORT SMITH, AR 72913-3880
PO BOX 3881, FORT SMITH, AR 72913-3881
PO BOX 3882, FORT SMITH, AR 72913-3882
PO BOX 3883, FORT SMITH, AR 72913-3883
PO BOX 3884, FORT SMITH, AR 72913-3884
PO BOX 3885, FORT SMITH, AR 72913-3885
PO BOX 3886, FORT SMITH, AR 72913-3886
PO BOX 3887, FORT SMITH, AR 72913-3887
PO BOX 3888, FORT SMITH, AR 72913-3888
PO BOX 3889, FORT SMITH, AR 72913-3889
PO BOX 3890, FORT SMITH, AR 72913-3890
PO BOX 3891, FORT SMITH, AR 72913-3891
PO BOX 3892, FORT SMITH, AR 72913-3892
PO BOX 3893, FORT SMITH, AR 72913-3893
PO BOX 3894, FORT SMITH, AR 72913-3894
PO BOX 3895, FORT SMITH, AR 72913-3895
PO BOX 3896, FORT SMITH, AR 72913-3896
PO BOX 3897, FORT SMITH, AR 72913-3897
PO BOX 3898, FORT SMITH, AR 72913-3898
PO BOX 3899, FORT SMITH, AR 72913-3899
PO BOX 3900, FORT SMITH, AR 72913-3900
PO BOX 3901, FORT SMITH, AR 72913-3901
PO BOX 3902, FORT SMITH, AR 72913-3902
PO BOX 3903, FORT SMITH, AR 72913-3903
PO BOX 3904, FORT SMITH, AR 72913-3904
PO BOX 3905, FORT SMITH, AR 72913-3905
PO BOX 3906, FORT SMITH, AR 72913-3906
PO BOX 3907, FORT SMITH, AR 72913-3907
PO BOX 3908, FORT SMITH, AR 72913-3908
PO BOX 3909, FORT SMITH, AR 72913-3909
PO BOX 3910, FORT SMITH, AR 72913-3910
PO BOX 3911, FORT SMITH, AR 72913-3911
PO BOX 3912, FORT SMITH, AR 72913-3912
PO BOX 3913, FORT SMITH, AR 72913-3913
PO BOX 3914, FORT SMITH, AR 72913-3914
PO BOX 3915, FORT SMITH, AR 72913-3915
PO BOX 3916, FORT SMITH, AR 72913-3916
PO BOX 3917, FORT SMITH, AR 72913-3917
PO BOX 3918, FORT SMITH, AR 72913-3918
PO BOX 3919, FORT SMITH, AR 72913-3919
PO BOX 3920, FORT SMITH, AR 72913-3920
PO BOX 3921, FORT SMITH, AR 72913-3921
PO BOX 3922, FORT SMITH, AR 72913-3922
PO BOX 3923, FORT SMITH, AR 72913-3923
PO BOX 3924, FORT SMITH, AR 72913-3924
PO BOX 3925, FORT SMITH, AR 72913-3925
PO BOX 3926, FORT SMITH, AR 72913-3926
PO BOX 3927, FORT SMITH, AR 72913-3927
PO BOX 3928, FORT SMITH, AR 72913-3928
PO BOX 3929, FORT SMITH, AR 72913-3929
PO BOX 3930, FORT SMITH, AR 72913-3930
PO BOX 3931, FORT SMITH, AR 72913-3931
PO BOX 3932, FORT SMITH, AR 72913-3932
PO BOX 3933, FORT SMITH, AR 72913-3933
PO BOX 3934, FORT SMITH, AR 72913-3934
PO BOX 3935, FORT SMITH, AR 72913-3935
PO BOX 3936, FORT SMITH, AR 72913-3936
PO BOX 3937, FORT SMITH, AR 72913-3937
PO BOX 3938, FORT SMITH, AR 72913-3938
PO BOX 3939, FORT SMITH, AR 72913-3939
PO BOX 3940, FORT SMITH, AR 72913-3940
PO BOX 3941, FORT SMITH, AR 72913-3941
PO BOX 3942, FORT SMITH, AR 72913-3942
PO BOX 3943, FORT SMITH, AR 72913-3943
PO BOX 3944, FORT SMITH, AR 72913-3944
PO BOX 3945, FORT SMITH, AR 72913-3945
PO BOX 3946, FORT SMITH, AR 72913-3946
PO BOX 3947, FORT SMITH, AR 72913-3947
PO BOX 3948, FORT SMITH, AR 72913-3948
PO BOX 3949, FORT SMITH, AR 72913-3949
PO BOX 3950, FORT SMITH, AR 72913-3950
PO BOX 3951, FORT SMITH, AR 72913-3951
PO BOX 3952, FORT SMITH, AR 72913-3952
PO BOX 3953, FORT SMITH, AR 72913-3953
PO BOX 3954, FORT SMITH, AR 72913-3954
PO BOX 3955, FORT SMITH, AR 72913-3955
PO BOX 3956, FORT SMITH, AR 72913-3956
PO BOX 3957, FORT SMITH, AR 72913-3957
PO BOX 3958, FORT SMITH, AR 72913-3958
PO BOX 3959, FORT SMITH, AR 72913-3959
PO BOX 3960, FORT SMITH, AR 72913-3960
PO BOX 3961, FORT SMITH, AR 72913-3961
PO BOX 3962, FORT SMITH, AR 72913-3962
PO BOX 3963, FORT SMITH, AR 72913-3963
PO BOX 3964, FORT SMITH, AR 72913-3964
PO BOX 3965, FORT SMITH, AR 72913-3965
PO BOX 3966, FORT SMITH, AR 72913-3966
PO BOX 3967, FORT SMITH, AR 72913-3967
PO BOX 3968, FORT SMITH, AR 72913-3968
PO BOX 3969, FORT SMITH, AR 72913-3969
PO BOX 3970, FORT SMITH, AR 72913-3970
PO BOX 3971, FORT SMITH, AR 72913-3971
PO BOX 3972, FORT SMITH, AR 72913-3972
PO BOX 3973, FORT SMITH, AR 72913-3973
PO BOX 3974, FORT SMITH, AR 72913-3974
PO BOX 3975, FORT SMITH, AR 72913-3975
PO BOX 3976, FORT SMITH, AR 72913-3976
PO BOX 3977, FORT SMITH, AR 72913-3977
PO BOX 3978, FORT SMITH, AR 72913-3978
PO BOX 3979, FORT SMITH, AR 72913-3979
PO BOX 3980, FORT SMITH, AR 72913-3980
PO BOX 3981, FORT SMITH, AR 72913-3981
PO BOX 3982, FORT SMITH, AR 72913-3982
PO BOX 3983, FORT SMITH, AR 72913-3983
PO BOX 3984, FORT SMITH, AR 72913-3984
PO BOX 3985, FORT SMITH, AR 72913-3985
PO BOX 3986, FORT SMITH, AR 72913-3986
PO BOX 3987, FORT SMITH, AR 72913-3987
PO BOX 3988, FORT SMITH, AR 72913-3988
PO BOX 3989, FORT SMITH, AR 72913-3989
PO BOX 3990, FORT SMITH, AR 72913-3990
PO BOX 3991, FORT SMITH, AR 72913-3991
PO BOX 3992, FORT SMITH, AR 72913-3992
PO BOX 3993, FORT SMITH, AR 72913-3993
PO BOX 3994, FORT SMITH, AR 72913-3994
PO BOX 3995, FORT SMITH, AR 72913-3995
PO BOX 3996, FORT SMITH, AR 72913-3996
PO BOX 3997, FORT SMITH, AR 72913-3997
PO BOX 3998, FORT SMITH, AR 72913-3998
PO BOX 3999, FORT SMITH, AR 72913-3999