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 659500, DALLAS, TX 75265-1600
PO BOX 659501, DALLAS, TX 75265-1601
PO BOX 659502, DALLAS, TX 75265-1602
PO BOX 659503, DALLAS, TX 75265-1603
PO BOX 659504, DALLAS, TX 75265-1604
PO BOX 659505, DALLAS, TX 75265-1605
PO BOX 659506, DALLAS, TX 75265-1606
PO BOX 659507, DALLAS, TX 75265-1607
PO BOX 659508, DALLAS, TX 75265-1608
PO BOX 659509, DALLAS, TX 75265-1609
PO BOX 659510, DALLAS, TX 75265-1610
PO BOX 659511, DALLAS, TX 75265-1611
PO BOX 659512, DALLAS, TX 75265-1612
PO BOX 659513, DALLAS, TX 75265-1613
PO BOX 659514, DALLAS, TX 75265-1614
PO BOX 659515, DALLAS, TX 75265-1615
PO BOX 659516, DALLAS, TX 75265-1616
PO BOX 659517, DALLAS, TX 75265-1617
PO BOX 659518, DALLAS, TX 75265-1618
PO BOX 659519, DALLAS, TX 75265-1619
PO BOX 659520, DALLAS, TX 75265-1620
PO BOX 659521, DALLAS, TX 75265-1621
PO BOX 659522, DALLAS, TX 75265-1622
PO BOX 659523, DALLAS, TX 75265-1623
PO BOX 659524, DALLAS, TX 75265-1624
PO BOX 659525, DALLAS, TX 75265-1625
PO BOX 659526, DALLAS, TX 75265-1626
PO BOX 659527, DALLAS, TX 75265-1627
PO BOX 659528, DALLAS, TX 75265-1628
PO BOX 659529, DALLAS, TX 75265-1629
PO BOX 659530, DALLAS, TX 75265-1630
PO BOX 659531, DALLAS, TX 75265-1631
PO BOX 659532, DALLAS, TX 75265-1632
PO BOX 659533, DALLAS, TX 75265-1633
PO BOX 659534, DALLAS, TX 75265-1634
PO BOX 659535, DALLAS, TX 75265-1635
PO BOX 659536, DALLAS, TX 75265-1636
PO BOX 659537, DALLAS, TX 75265-1637
PO BOX 659538, DALLAS, TX 75265-1638
PO BOX 659539, DALLAS, TX 75265-1639
PO BOX 659540, DALLAS, TX 75265-1640
PO BOX 659541, DALLAS, TX 75265-1641
PO BOX 659542, DALLAS, TX 75265-1642
PO BOX 659543, DALLAS, TX 75265-1643
PO BOX 659544, DALLAS, TX 75265-1644
PO BOX 659545, DALLAS, TX 75265-1645
PO BOX 659546, DALLAS, TX 75265-1646
PO BOX 659547, DALLAS, TX 75265-1647
PO BOX 659548, DALLAS, TX 75265-1648
PO BOX 659549, DALLAS, TX 75265-1649
PO BOX 659550, DALLAS, TX 75265-1650
PO BOX 659551, DALLAS, TX 75265-1651
PO BOX 659552, DALLAS, TX 75265-1652
PO BOX 659553, DALLAS, TX 75265-1653
PO BOX 659554, DALLAS, TX 75265-1654
PO BOX 659555, DALLAS, TX 75265-1655
PO BOX 659556, DALLAS, TX 75265-1656
PO BOX 659557, DALLAS, TX 75265-1657
PO BOX 659558, DALLAS, TX 75265-1658
PO BOX 659559, DALLAS, TX 75265-1659
PO BOX 659560, DALLAS, TX 75265-1660
PO BOX 659561, DALLAS, TX 75265-1661
PO BOX 659562, DALLAS, TX 75265-1662
PO BOX 659563, DALLAS, TX 75265-1663
PO BOX 659564, DALLAS, TX 75265-1664
PO BOX 659565, DALLAS, TX 75265-1665
PO BOX 659566, DALLAS, TX 75265-1666
PO BOX 659567, DALLAS, TX 75265-1667
PO BOX 659568, DALLAS, TX 75265-1668
PO BOX 659569, DALLAS, TX 75265-1669
PO BOX 659570, DALLAS, TX 75265-1670
PO BOX 659571, DALLAS, TX 75265-1671
PO BOX 659572, DALLAS, TX 75265-1672
PO BOX 659573, DALLAS, TX 75265-1673
PO BOX 659574, DALLAS, TX 75265-1674
PO BOX 659575, DALLAS, TX 75265-1675
PO BOX 659576, DALLAS, TX 75265-1676
PO BOX 659577, DALLAS, TX 75265-1677
PO BOX 659578, DALLAS, TX 75265-1678
PO BOX 659579, DALLAS, TX 75265-1679
PO BOX 659580, DALLAS, TX 75265-1680
PO BOX 659581, DALLAS, TX 75265-1681
PO BOX 659582, DALLAS, TX 75265-1682
PO BOX 659583, DALLAS, TX 75265-1683
PO BOX 659584, DALLAS, TX 75265-1684
PO BOX 659585, DALLAS, TX 75265-1685
PO BOX 659586, DALLAS, TX 75265-1686
PO BOX 659587, DALLAS, TX 75265-1687
PO BOX 659588, DALLAS, TX 75265-1688
PO BOX 659589, DALLAS, TX 75265-1689
PO BOX 659590, DALLAS, TX 75265-1690
PO BOX 659591, DALLAS, TX 75265-1691
PO BOX 659592, DALLAS, TX 75265-1692
PO BOX 659593, DALLAS, TX 75265-1693
PO BOX 659594, DALLAS, TX 75265-1694
PO BOX 659595, DALLAS, TX 75265-1695
PO BOX 659596, DALLAS, TX 75265-1696
PO BOX 659597, DALLAS, TX 75265-1697
PO BOX 659598, DALLAS, TX 75265-1698
PO BOX 659599, DALLAS, TX 75265-1699
PO BOX 659600, DALLAS, TX 75265-1700
PO BOX 659601, DALLAS, TX 75265-1701
PO BOX 659602, DALLAS, TX 75265-1702
PO BOX 659603, DALLAS, TX 75265-1703
PO BOX 659604, DALLAS, TX 75265-1704
PO BOX 659605, DALLAS, TX 75265-1705
PO BOX 659606, DALLAS, TX 75265-1706
PO BOX 659607, DALLAS, TX 75265-1707
PO BOX 659608, DALLAS, TX 75265-1708
PO BOX 659609, DALLAS, TX 75265-1709
PO BOX 659610, DALLAS, TX 75265-1710
PO BOX 659611, DALLAS, TX 75265-1711
PO BOX 659612, DALLAS, TX 75265-1712
PO BOX 659613, DALLAS, TX 75265-1713
PO BOX 659614, DALLAS, TX 75265-1714
PO BOX 659615, DALLAS, TX 75265-1715
PO BOX 659616, DALLAS, TX 75265-1716
PO BOX 659617, DALLAS, TX 75265-1717
PO BOX 659618, DALLAS, TX 75265-1718
PO BOX 659619, DALLAS, TX 75265-1719
PO BOX 659620, DALLAS, TX 75265-1720
PO BOX 659621, DALLAS, TX 75265-1721
PO BOX 659622, DALLAS, TX 75265-1722
PO BOX 659623, DALLAS, TX 75265-1723
PO BOX 659624, DALLAS, TX 75265-1724
PO BOX 659625, DALLAS, TX 75265-1725
PO BOX 659626, DALLAS, TX 75265-1726
PO BOX 659627, DALLAS, TX 75265-1727
PO BOX 659628, DALLAS, TX 75265-1728
PO BOX 659629, DALLAS, TX 75265-1729
PO BOX 659630, DALLAS, TX 75265-1730
PO BOX 659631, DALLAS, TX 75265-1731
PO BOX 659632, DALLAS, TX 75265-1732
PO BOX 659633, DALLAS, TX 75265-1733
PO BOX 659634, DALLAS, TX 75265-1734
PO BOX 659635, DALLAS, TX 75265-1735
PO BOX 659636, DALLAS, TX 75265-1736
PO BOX 659637, DALLAS, TX 75265-1737
PO BOX 659638, DALLAS, TX 75265-1738
PO BOX 659639, DALLAS, TX 75265-1739
PO BOX 659640, DALLAS, TX 75265-1740
PO BOX 659641, DALLAS, TX 75265-1741
PO BOX 659642, DALLAS, TX 75265-1742
PO BOX 659643, DALLAS, TX 75265-1743
PO BOX 659644, DALLAS, TX 75265-1744
PO BOX 659645, DALLAS, TX 75265-1745
PO BOX 659646, DALLAS, TX 75265-1746
PO BOX 659647, DALLAS, TX 75265-1747
PO BOX 659648, DALLAS, TX 75265-1748
PO BOX 659649, DALLAS, TX 75265-1749
PO BOX 659650, DALLAS, TX 75265-1750
PO BOX 659651, DALLAS, TX 75265-1751
PO BOX 659652, DALLAS, TX 75265-1752
PO BOX 659653, DALLAS, TX 75265-1753
PO BOX 659654, DALLAS, TX 75265-1754
PO BOX 659655, DALLAS, TX 75265-1755
PO BOX 659656, DALLAS, TX 75265-1756
PO BOX 659657, DALLAS, TX 75265-1757
PO BOX 659658, DALLAS, TX 75265-1758
PO BOX 659659, DALLAS, TX 75265-1759
PO BOX 659660, DALLAS, TX 75265-1760
PO BOX 659661, DALLAS, TX 75265-1761
PO BOX 659662, DALLAS, TX 75265-1762
PO BOX 659663, DALLAS, TX 75265-1763
PO BOX 659664, DALLAS, TX 75265-1764
PO BOX 659665, DALLAS, TX 75265-1765
PO BOX 659666, DALLAS, TX 75265-1766
PO BOX 659667, DALLAS, TX 75265-1767
PO BOX 659668, DALLAS, TX 75265-1768
PO BOX 659669, DALLAS, TX 75265-1769
PO BOX 659670, DALLAS, TX 75265-1770
PO BOX 659671, DALLAS, TX 75265-1771
PO BOX 659672, DALLAS, TX 75265-1772
PO BOX 659673, DALLAS, TX 75265-1773
PO BOX 659674, DALLAS, TX 75265-1774
PO BOX 659675, DALLAS, TX 75265-1775
PO BOX 659676, DALLAS, TX 75265-1776
PO BOX 659677, DALLAS, TX 75265-1777
PO BOX 659678, DALLAS, TX 75265-1778
PO BOX 659679, DALLAS, TX 75265-1779
PO BOX 659680, DALLAS, TX 75265-1780
PO BOX 659681, DALLAS, TX 75265-1781
PO BOX 659682, DALLAS, TX 75265-1782
PO BOX 659683, DALLAS, TX 75265-1783
PO BOX 659684, DALLAS, TX 75265-1784
PO BOX 659685, DALLAS, TX 75265-1785
PO BOX 659686, DALLAS, TX 75265-1786
PO BOX 659687, DALLAS, TX 75265-1787
PO BOX 659688, DALLAS, TX 75265-1788
PO BOX 659689, DALLAS, TX 75265-1789
PO BOX 659690, DALLAS, TX 75265-1790
PO BOX 659691, DALLAS, TX 75265-1791
PO BOX 659692, DALLAS, TX 75265-1792
PO BOX 659693, DALLAS, TX 75265-1793
PO BOX 659694, DALLAS, TX 75265-1794
PO BOX 659695, DALLAS, TX 75265-1795
PO BOX 659696, DALLAS, TX 75265-1796
PO BOX 659697, DALLAS, TX 75265-1797
PO BOX 659698, DALLAS, TX 75265-1798
PO BOX 659699, DALLAS, TX 75265-1799
PO BOX 659700, DALLAS, TX 75265-1800