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 3161, FORT SMITH, AR 72913-3161
PO BOX 3162, FORT SMITH, AR 72913-3162
PO BOX 3163, FORT SMITH, AR 72913-3163
PO BOX 3164, FORT SMITH, AR 72913-3164
PO BOX 3165, FORT SMITH, AR 72913-3165
PO BOX 3166, FORT SMITH, AR 72913-3166
PO BOX 3167, FORT SMITH, AR 72913-3167
PO BOX 3168, FORT SMITH, AR 72913-3168
PO BOX 3169, FORT SMITH, AR 72913-3169
PO BOX 3170, FORT SMITH, AR 72913-3170
PO BOX 3171, FORT SMITH, AR 72913-3171
PO BOX 3172, FORT SMITH, AR 72913-3172
PO BOX 3173, FORT SMITH, AR 72913-3173
PO BOX 3174, FORT SMITH, AR 72913-3174
PO BOX 3175, FORT SMITH, AR 72913-3175
PO BOX 3176, FORT SMITH, AR 72913-3176
PO BOX 3177, FORT SMITH, AR 72913-3177
PO BOX 3178, FORT SMITH, AR 72913-3178
PO BOX 3179, FORT SMITH, AR 72913-3179
PO BOX 3180, FORT SMITH, AR 72913-3180
PO BOX 3181, FORT SMITH, AR 72913-3181
PO BOX 3182, FORT SMITH, AR 72913-3182
PO BOX 3183, FORT SMITH, AR 72913-3183
PO BOX 3184, FORT SMITH, AR 72913-3184
PO BOX 3185, FORT SMITH, AR 72913-3185
PO BOX 3186, FORT SMITH, AR 72913-3186
PO BOX 3187, FORT SMITH, AR 72913-3187
PO BOX 3188, FORT SMITH, AR 72913-3188
PO BOX 3189, FORT SMITH, AR 72913-3189
PO BOX 3190, FORT SMITH, AR 72913-3190
PO BOX 3191, FORT SMITH, AR 72913-3191
PO BOX 3192, FORT SMITH, AR 72913-3192
PO BOX 3193, FORT SMITH, AR 72913-3193
PO BOX 3194, FORT SMITH, AR 72913-3194
PO BOX 3195, FORT SMITH, AR 72913-3195
PO BOX 3196, FORT SMITH, AR 72913-3196
PO BOX 3197, FORT SMITH, AR 72913-3197
PO BOX 3198, FORT SMITH, AR 72913-3198
PO BOX 3199, FORT SMITH, AR 72913-3199
PO BOX 3200, FORT SMITH, AR 72913-3200
PO BOX 3201, FORT SMITH, AR 72913-3201
PO BOX 3202, FORT SMITH, AR 72913-3202
PO BOX 3203, FORT SMITH, AR 72913-3203
PO BOX 3204, FORT SMITH, AR 72913-3204
PO BOX 3205, FORT SMITH, AR 72913-3205
PO BOX 3206, FORT SMITH, AR 72913-3206
PO BOX 3207, FORT SMITH, AR 72913-3207
PO BOX 3208, FORT SMITH, AR 72913-3208
PO BOX 3209, FORT SMITH, AR 72913-3209
PO BOX 3210, FORT SMITH, AR 72913-3210
PO BOX 3211, FORT SMITH, AR 72913-3211
PO BOX 3212, FORT SMITH, AR 72913-3212
PO BOX 3213, FORT SMITH, AR 72913-3213
PO BOX 3214, FORT SMITH, AR 72913-3214
PO BOX 3215, FORT SMITH, AR 72913-3215
PO BOX 3216, FORT SMITH, AR 72913-3216
PO BOX 3217, FORT SMITH, AR 72913-3217
PO BOX 3218, FORT SMITH, AR 72913-3218
PO BOX 3219, FORT SMITH, AR 72913-3219
PO BOX 3220, FORT SMITH, AR 72913-3220
PO BOX 3221, FORT SMITH, AR 72913-3221
PO BOX 3222, FORT SMITH, AR 72913-3222
PO BOX 3223, FORT SMITH, AR 72913-3223
PO BOX 3224, FORT SMITH, AR 72913-3224
PO BOX 3225, FORT SMITH, AR 72913-3225
PO BOX 3226, FORT SMITH, AR 72913-3226
PO BOX 3227, FORT SMITH, AR 72913-3227
PO BOX 3228, FORT SMITH, AR 72913-3228
PO BOX 3229, FORT SMITH, AR 72913-3229
PO BOX 3230, FORT SMITH, AR 72913-3230
PO BOX 3231, FORT SMITH, AR 72913-3231
PO BOX 3232, FORT SMITH, AR 72913-3232
PO BOX 3233, FORT SMITH, AR 72913-3233
PO BOX 3234, FORT SMITH, AR 72913-3234
PO BOX 3235, FORT SMITH, AR 72913-3235
PO BOX 3236, FORT SMITH, AR 72913-3236
PO BOX 3237, FORT SMITH, AR 72913-3237
PO BOX 3238, FORT SMITH, AR 72913-3238
PO BOX 3239, FORT SMITH, AR 72913-3239
PO BOX 3240, FORT SMITH, AR 72913-3240
PO BOX 3241, FORT SMITH, AR 72913-3241
PO BOX 3242, FORT SMITH, AR 72913-3242
PO BOX 3243, FORT SMITH, AR 72913-3243
PO BOX 3244, FORT SMITH, AR 72913-3244
PO BOX 3245, FORT SMITH, AR 72913-3245
PO BOX 3246, FORT SMITH, AR 72913-3246
PO BOX 3247, FORT SMITH, AR 72913-3247
PO BOX 3248, FORT SMITH, AR 72913-3248
PO BOX 3249, FORT SMITH, AR 72913-3249
PO BOX 3250, FORT SMITH, AR 72913-3250
PO BOX 3251, FORT SMITH, AR 72913-3251
PO BOX 3252, FORT SMITH, AR 72913-3252
PO BOX 3253, FORT SMITH, AR 72913-3253
PO BOX 3254, FORT SMITH, AR 72913-3254
PO BOX 3255, FORT SMITH, AR 72913-3255
PO BOX 3256, FORT SMITH, AR 72913-3256
PO BOX 3257, FORT SMITH, AR 72913-3257
PO BOX 3258, FORT SMITH, AR 72913-3258
PO BOX 3259, FORT SMITH, AR 72913-3259
PO BOX 3260, FORT SMITH, AR 72913-3260
PO BOX 3261, FORT SMITH, AR 72913-3261
PO BOX 3262, FORT SMITH, AR 72913-3262
PO BOX 3263, FORT SMITH, AR 72913-3263
PO BOX 3264, FORT SMITH, AR 72913-3264
PO BOX 3265, FORT SMITH, AR 72913-3265
PO BOX 3266, FORT SMITH, AR 72913-3266
PO BOX 3267, FORT SMITH, AR 72913-3267
PO BOX 3268, FORT SMITH, AR 72913-3268
PO BOX 3269, FORT SMITH, AR 72913-3269
PO BOX 3270, FORT SMITH, AR 72913-3270
PO BOX 3271, FORT SMITH, AR 72913-3271
PO BOX 3272, FORT SMITH, AR 72913-3272
PO BOX 3273, FORT SMITH, AR 72913-3273
PO BOX 3274, FORT SMITH, AR 72913-3274
PO BOX 3275, FORT SMITH, AR 72913-3275
PO BOX 3276, FORT SMITH, AR 72913-3276
PO BOX 3277, FORT SMITH, AR 72913-3277
PO BOX 3278, FORT SMITH, AR 72913-3278
PO BOX 3279, FORT SMITH, AR 72913-3279
PO BOX 3280, FORT SMITH, AR 72913-3280
PO BOX 3281, FORT SMITH, AR 72913-3281
PO BOX 3282, FORT SMITH, AR 72913-3282
PO BOX 3283, FORT SMITH, AR 72913-3283
PO BOX 3284, FORT SMITH, AR 72913-3284
PO BOX 3285, FORT SMITH, AR 72913-3285
PO BOX 3286, FORT SMITH, AR 72913-3286
PO BOX 3287, FORT SMITH, AR 72913-3287
PO BOX 3288, FORT SMITH, AR 72913-3288
PO BOX 3289, FORT SMITH, AR 72913-3289
PO BOX 3290, FORT SMITH, AR 72913-3290
PO BOX 3291, FORT SMITH, AR 72913-3291
PO BOX 3292, FORT SMITH, AR 72913-3292
PO BOX 3293, FORT SMITH, AR 72913-3293
PO BOX 3294, FORT SMITH, AR 72913-3294
PO BOX 3295, FORT SMITH, AR 72913-3295
PO BOX 3296, FORT SMITH, AR 72913-3296
PO BOX 3297, FORT SMITH, AR 72913-3297
PO BOX 3298, FORT SMITH, AR 72913-3298
PO BOX 3299, FORT SMITH, AR 72913-3299
PO BOX 3300, FORT SMITH, AR 72913-3300
PO BOX 3301, FORT SMITH, AR 72913-3301
PO BOX 3302, FORT SMITH, AR 72913-3302
PO BOX 3303, FORT SMITH, AR 72913-3303
PO BOX 3304, FORT SMITH, AR 72913-3304
PO BOX 3305, FORT SMITH, AR 72913-3305
PO BOX 3306, FORT SMITH, AR 72913-3306
PO BOX 3307, FORT SMITH, AR 72913-3307
PO BOX 3308, FORT SMITH, AR 72913-3308
PO BOX 3309, FORT SMITH, AR 72913-3309
PO BOX 3310, FORT SMITH, AR 72913-3310
PO BOX 3311, FORT SMITH, AR 72913-3311
PO BOX 3312, FORT SMITH, AR 72913-3312
PO BOX 3313, FORT SMITH, AR 72913-3313
PO BOX 3314, FORT SMITH, AR 72913-3314
PO BOX 3315, FORT SMITH, AR 72913-3315
PO BOX 3316, FORT SMITH, AR 72913-3316
PO BOX 3317, FORT SMITH, AR 72913-3317
PO BOX 3318, FORT SMITH, AR 72913-3318
PO BOX 3319, FORT SMITH, AR 72913-3319
PO BOX 3320, FORT SMITH, AR 72913-3320
PO BOX 3321, FORT SMITH, AR 72913-3321
PO BOX 3322, FORT SMITH, AR 72913-3322
PO BOX 3323, FORT SMITH, AR 72913-3323
PO BOX 3324, FORT SMITH, AR 72913-3324
PO BOX 3325, FORT SMITH, AR 72913-3325
PO BOX 3326, FORT SMITH, AR 72913-3326
PO BOX 3327, FORT SMITH, AR 72913-3327
PO BOX 3328, FORT SMITH, AR 72913-3328
PO BOX 3329, FORT SMITH, AR 72913-3329
PO BOX 3330, FORT SMITH, AR 72913-3330
PO BOX 3331, FORT SMITH, AR 72913-3331
PO BOX 3332, FORT SMITH, AR 72913-3332
PO BOX 3333, FORT SMITH, AR 72913-3333
PO BOX 3334, FORT SMITH, AR 72913-3334
PO BOX 3335, FORT SMITH, AR 72913-3335
PO BOX 3336, FORT SMITH, AR 72913-3336
PO BOX 3337, FORT SMITH, AR 72913-3337
PO BOX 3338, FORT SMITH, AR 72913-3338
PO BOX 3339, FORT SMITH, AR 72913-3339
PO BOX 3340, FORT SMITH, AR 72913-3340
PO BOX 3341, FORT SMITH, AR 72913-3341
PO BOX 3342, FORT SMITH, AR 72913-3342
PO BOX 3343, FORT SMITH, AR 72913-3343
PO BOX 3344, FORT SMITH, AR 72913-3344
PO BOX 3345, FORT SMITH, AR 72913-3345
PO BOX 3346, FORT SMITH, AR 72913-3346
PO BOX 3347, FORT SMITH, AR 72913-3347
PO BOX 3348, FORT SMITH, AR 72913-3348
PO BOX 3349, FORT SMITH, AR 72913-3349
PO BOX 3350, FORT SMITH, AR 72913-3350
PO BOX 3351, FORT SMITH, AR 72913-3351
PO BOX 3352, FORT SMITH, AR 72913-3352
PO BOX 3353, FORT SMITH, AR 72913-3353
PO BOX 3354, FORT SMITH, AR 72913-3354
PO BOX 3355, FORT SMITH, AR 72913-3355
PO BOX 3356, FORT SMITH, AR 72913-3356
PO BOX 3357, FORT SMITH, AR 72913-3357
PO BOX 3358, FORT SMITH, AR 72913-3358
PO BOX 3359, FORT SMITH, AR 72913-3359
PO BOX 3360, FORT SMITH, AR 72913-3360
PO BOX 3361, FORT SMITH, AR 72913-3361