Any coding scheme that does not provide for well defined updating procedures ultimately becomes obsolete and loses its relevance to the information system it intends to serve. In the updating of the Philippine Standard Geographic Code, the following cases were/should be considered:
Changes at the Region Level
Creation of a New Region. A new region that may be created will assume codes corresponding to its region numbers. While autonomous regions will be assigned codes in descending order. Thus, NCR (National Capital Region) was assigned code 99, Cordillera Administrative Region (CAR) code was 98 and Autonomous Region in Muslim Mindanao (ARMM) was 97. For example, the last entry for autonomous regions is 97 for ARMM, the next region will be assigned the Region Code 96.
Fragmentation of a Region. When a region is fragmented into 2 or more autonomous regions, the original region or the region which retains the seat of regional offices of the Departments of the Executive Branch of the Government, retains its Region Code and the other region created out of this fragmentation shall be treated as a new region and shall be assigned a code number next to the last entry in the series.
Merger. It is a possibility that two regions may be merged to form one region. In this case, convention requires that one of the two regions will arbitrarily be treated as a "predominant region". The predominant region retains its Region Code, which will then represent the resulting merger. The other region will lose its Region Code. In case such merger is subsequently dissolved, the predominant region retains its original code and the other region assumes its former code.
Change of Name. Regions are given a Region number and at the same time a general descriptive clause to describe the area. For example: Region 6 has a descriptive clause, Western Visayas attached to it. In such case, where the descriptive clause is changed, without any change in the regional boundary lines, the Region Code remains the same.
Changes at the Province Level
Creation of a New Province. Any new province that may be created will assume a Province Code that is next to the last entry in the current series. For example: the last Province Code as of December 31, 1995 is 81 for Apayao. The next province that may be created will have the Province Code 82.
Fragmentation of a Province. A province may be fragmented to form two or more provinces. The original/parent province shall retain its Province Code. The other province that may be created as a result of this fragmentation shall be treated as a new province and shall be assigned a new Province Code in accordance with the procedure in the Creation of a New Province.
Merger. A situation may arise where two provinces are merged to form one province. In this case, one of the provinces is arbitrarily designated as the "predominant province" which shall represent the resulting merger. The new province resulting from such merger will assume the Province Code of the predominant province, while the other will lose its Province Code. In case the merger is subsequently dissolved, the predominant province retain its original code while the other province assume its former code.
Change of Name. If the name of the Province is changed (e.g., Tayabas was renamed as Quezon Province), the Province Code remains the same for as long as there is no change in the boundary lines of the province.
Transfer to Another Region. In the case where a province is transferred to another region, there shall be no change in the Province Code. The transfer to another region will only cause a change in the corresponding Region Code for that province.
Changes at the Municipality Level
Creation of New Municipalities. Within the province, a new municipality that may be created will be assigned a Municipality Code which is next to the last number in the current series. For example, in the province of Cebu the last Municipality Code is 53 (Municipality Identifier 2253 for Tudela, Cebu). The next municipality that may be created in Cebu will have the Municipality Code 54 (Municipality Identifier 2254). If two or more municipalities are created simultaneously, they shall be assigned codes sequentially following their alphabetic order, otherwise, they will be assigned codes according to the dates of their creation.
Fragmentation of a Municipality. A given municipality may be fragmented to form two or more municipalities. In this case, the originating/parent municipality retains its Municipality Code. The new municipality/ies that may be created out of this fragmentation will be treated as new municipality/ies, and shall assume a new Municipality Code/s as in the case of creation of a new municipality/ies in accordance with the procedure in the Creation of New Municipalities.
Merger. In cases where two or more municipalities were merged to form just one municipality, one of the municipalities is arbitrarily designated as the "predominant municipality". The predominant municipality shall represent the total domain of the resulting merger, and retains its municipality code while the others will lose their respective codes. In case the merger is subsequently dissolved, the original municipalities will assume their former codes.
Change of Name. A change in the name of a municipality will not effect any change in the Municipality Code, provided that the municipality boundary lines remain the same.
Transfer to Another Province. When a municipality is transferred to another province, this will of course mean a change in the Municipality Code. Such municipality shall be treated as a newly created municipality within that province and shall be assigned a new code following the procedure in the Creation of a New Municipality. The Municipality Identifier will now be based on the Province Code of its new province and the new code of the municipality. In case such municipality is returned back to its original province, it shall resume its original Municipality Identifier.
Suppose Norala, South Cotabato is transferred to the adjacent province of Sultan Kudarat.
Present Municipality Identifier : 6311
New Municipality Identifier : 6513
Changes at Barangay Level
Creation of New Barangays. When a new barangay is created within a municipality, it shall assume a barangay code which is next to the last number in the current series. Thus, if the last barangay code is 072, the next barangay that will be created will assume Barangay Code 073. If two or more new barangays are created simultaneously within a municipality, the newly created barangays shall be assigned codes sequentially following their alphabetic or numeric order (e.g., Barangay 1, Barangay 2, etc.) starting from the next to the last code number in the current series, otherwise, they will be assigned codes according to the sequence of the dates of their creation.
Fragmentation of a Barangay. A barangay may be fragmented to form two or more barangays. In this case, the originating/parent barangay shall retain its Barangay Code. The new barangay/s created out of the fragmentation shall be treated as newly created barangay/s and shall be assigned new Barangay Code/s in accordance with the procedure in the Creation of New Barangays.
Merger. Two or more barangays may be merged to form one barangay. As a matter of convention, one of the barangays involved in the merger is designated as the "predominant barangay" to represent the whole domain of the merger. The resulting barangay formed out of the merger shall assume the Barangay Code of the predominant barangay. The rest of the barangays will lose their Barangay Codes. In case the merger is subsequently dissolved, the treatment shall be as in fragmentation of a barangay, with the barangays assuming their former codes.
Change of Name. A change in barangay name will not entail any change in Barangay Code provided that the domain of the barangay (i.e., boundary lines) is not altered.
Transfer to Another Municipality. Barangay/s transferred to another municipality shall be treated as newly created barangay/s and shall be assigned new code/s in accordance with the procedure in the Creation of a New Barangay. If the transfer is rescinded, the barangay/s will assume its/their original Barangay Code/s.