Reference

Virginia API county codes

Every Virginia API well number starts with 45, the state code. The next three digits are the county code, one of the 134 listed below, so a number beginning 45-001 belongs to a well in Accomack County.

To decode a whole number, including the sidetrack and completion digits, paste it into the API well number decoder.

How to read a Virginia API number

45State: Virginia
001County: Accomack
12345Well, unique within the county

The first ten digits identify one well. Two more digits can follow for a sidetrack, and two after that for a later completion. The county is the one where the well starts at the surface, so a horizontal well that crosses a county line keeps its surface county's code. A few state regulators assign the producing county instead, so the state record is the final word on a well near a boundary.

All 134 Virginia counties

County code County API numbers start
001 Accomack 45-001-
003 Albemarle 45-003-
005 Alleghany 45-005-
007 Amelia 45-007-
009 Amherst 45-009-
011 Appomattox 45-011-
013 Arlington 45-013-
015 Augusta 45-015-
017 Bath 45-017-
019 Bedford 45-019-
021 Bland 45-021-
023 Botetourt 45-023-
025 Brunswick 45-025-
027 Buchanan 45-027-
029 Buckingham 45-029-
031 Campbell 45-031-
033 Caroline 45-033-
035 Carroll 45-035-
036 Charles City 45-036-
037 Charlotte 45-037-
041 Chesterfield 45-041-
043 Clarke 45-043-
045 Craig 45-045-
047 Culpeper 45-047-
049 Cumberland 45-049-
051 Dickenson 45-051-
053 Dinwiddie 45-053-
057 Essex 45-057-
059 Fairfax 45-059-
061 Fauquier 45-061-
063 Floyd 45-063-
065 Fluvanna 45-065-
067 Franklin 45-067-
069 Frederick 45-069-
071 Giles 45-071-
073 Gloucester 45-073-
075 Goochland 45-075-
077 Grayson 45-077-
079 Greene 45-079-
081 Greensville 45-081-
083 Halifax 45-083-
085 Hanover 45-085-
087 Henrico 45-087-
089 Henry 45-089-
091 Highland 45-091-
093 Isle of Wight 45-093-
095 James City 45-095-
097 King and Queen 45-097-
099 King George 45-099-
101 King William 45-101-
103 Lancaster 45-103-
105 Lee 45-105-
107 Loudoun 45-107-
109 Louisa 45-109-
111 Lunenburg 45-111-
113 Madison 45-113-
115 Mathews 45-115-
117 Mecklenburg 45-117-
119 Middlesex 45-119-
121 Montgomery 45-121-
125 Nelson 45-125-
127 New Kent 45-127-
131 Northampton 45-131-
133 Northumberland 45-133-
135 Nottoway 45-135-
137 Orange 45-137-
139 Page 45-139-
141 Patrick 45-141-
143 Pittsylvania 45-143-
145 Powhatan 45-145-
147 Prince Edward 45-147-
149 Prince George 45-149-
153 Prince William 45-153-
155 Pulaski 45-155-
157 Rappahannock 45-157-
159 Richmond 45-159-
161 Roanoke 45-161-
163 Rockbridge 45-163-
165 Rockingham 45-165-
167 Russell 45-167-
169 Scott 45-169-
171 Shenandoah 45-171-
173 Smyth 45-173-
175 Southampton 45-175-
177 Spotsylvania 45-177-
179 Stafford 45-179-
181 Surry 45-181-
183 Sussex 45-183-
185 Tazewell 45-185-
187 Warren 45-187-
191 Washington 45-191-
193 Westmoreland 45-193-
195 Wise 45-195-
197 Wythe 45-197-
199 York 45-199-
510 Alexandria city 45-510-
515 Bedford city 45-515-
520 Bristol city 45-520-
530 Buena Vista city 45-530-
540 Charlottesville city 45-540-
550 Chesapeake city 45-550-
570 Colonial Heights city 45-570-
580 Covington city 45-580-
590 Danville city 45-590-
595 Emporia city 45-595-
600 Fairfax city 45-600-
610 Falls Church city 45-610-
620 Franklin city 45-620-
630 Fredericksburg city 45-630-
640 Galax city 45-640-
650 Hampton city 45-650-
660 Harrisonburg city 45-660-
670 Hopewell city 45-670-
678 Lexington city 45-678-
680 Lynchburg city 45-680-
683 Manassas city 45-683-
685 Manassas Park city 45-685-
690 Martinsville city 45-690-
700 Newport News city 45-700-
710 Norfolk city 45-710-
720 Norton city 45-720-
730 Petersburg city 45-730-
735 Poquoson city 45-735-
740 Portsmouth city 45-740-
750 Radford city 45-750-
760 Richmond city 45-760-
770 Roanoke city 45-770-
775 Salem city 45-775-
790 Staunton city 45-790-
800 Suffolk city 45-800-
810 Virginia Beach city 45-810-
820 Waynesboro city 45-820-
830 Williamsburg city 45-830-
840 Winchester city 45-840-

County names are the US Census names for these codes. The API standard does not promise the two match, so we checked them against state well records. Across 35 states, where this table names a county it matched the one the agency recorded on 85,091 of 85,100 wells. Offshore state and federal waters use their own pseudo-county codes, which are not listed here.

Finding the well itself

The API number stops at the county. It does not hold the well's coordinates, lease, survey section or operator. Those sit in the well record, which you find by searching the full number in the state agency's system. Search it at the Virginia oil and gas regulator.

Frequently asked questions

What is the API state code for Virginia?

45. API state codes run alphabetically from 01 for Alabama to 49 for Wyoming, then 50 for Alaska and 51 for Hawaii. They are not the Census FIPS state codes, which is a common source of wrong lookups.

How do I find the county from a Virginia API number?

Read digits three to five and find them in the table on this page. In 45-001-12345, the county code is 001, which is Accomack County. If the code is missing from the table, it is usually an offshore area rather than an onshore county.

Does a Virginia API number give the well's exact location?

No. The number stops at the county. Coordinates, the lease and the survey location are in the well record held by the state agency, which you search with the full API number.

State codes: American Petroleum Institute Bulletin D12A well numbering standard. County names: US Census county FIPS names, checked against state well records. Reference generated .

How to cite this page

Sources: American Petroleum Institute Bulletin D12A well numbering standard; US Census county FIPS codes.

TetraSoft. (2026). Virginia API county codes. Reference generated 2026-09-24. https://tetrasoftco.com/tools/api-county-codes/virginia/