# January 2026

## OSMM Topography Layer product count

The following table contains product counts for this release of OSMM Topography Layer data. The dates shown are extraction dates, not release dates.

| OSMM Topography Layer                | Count on 06/11/2025 (Last Release) | Count on 11/12/2025 (This Release) |
| ------------------------------------ | ---------------------------------- | ---------------------------------- |
| **Total Feature Count**              | **516 255 739**                    | **516 731 189**                    |
| Count of Topo Area                   | 129 179 335                        | 129 299 175                        |
| Count of Topo Line                   | 355 932 638                        | 356 273 836                        |
| Count of Topo Point                  | 4 462 725                          | 4 466 384                          |
| Count of Topo Bline                  | 520 570                            | 520 602                            |
| Count of Topo CartoSym               | 3 854 066                          | 3 859 375                          |
| Count of Topo CartoTxt               | 22 306 405                         | 22 311 817                         |
| **Total Count of Deletes**           | **836 866**                        | **598 529**                        |
| Count of Topo Area deletions         | 162 006                            | 113 839                            |
| Count of Topo Line deletions         | 612 392                            | 437 808                            |
| Count of Topo Point deletions        | 6 892                              | 4 995                              |
| Count of Topo Bline deletions        | 943                                | 281                                |
| Count of Topo CartoSym deletions     | 5 155                              | 2 984                              |
| Count of Topo CartoTxt deletions     | 49 478                             | 38 622                             |
| **Total Count of Inserts**           | **1 477 987**                      | **1 073 979**                      |
| Count of Topo Area inserts           | 323 318                            | 233 679                            |
| Count of Topo Line inserts           | 1 069 960                          | 779 006                            |
| Count of Topo Point inserts          | 14 540                             | 8 654                              |
| Count of Topo Bline inserts          | 608                                | 313                                |
| Count of Topo CartoSym inserts       | 14 207                             | 8 293                              |
| Count of Topo CartoTxt inserts       | 55 354                             | 44 034                             |
| **Total Count of Modifications**     | **1 407 831**                      | **1 038 366**                      |
| Count of Topo Area Modifications     | 715 622                            | 527 931                            |
| Count of Topo Line Modifications     | 673 769                            | 496 225                            |
| Count of Topo Point Modifications    | 1 110                              | 1 161                              |
| Count of Topo Bline Modifications    | 1 450                              | 404                                |
| Count of Topo CartoSym Modifications | 54                                 | 151                                |
| Count of Topo CartoTxt Modifications | 15 826                             | 12 494                             |
| **COU Size (bytes)**                 | **625 627 136**                    | **464 904 192**                    |

## Changed TOIDs

Numerous TOIDs (Topographic Identifiers) have changed since the last refresh, resulting in a visual difference in the data. The list below shows a sample of changed TOIDs and their locations that you can use as 'lookup samples' to validate that your latest supply has updated correctly:

<table><thead><tr><th width="373.6666259765625">TOID</th><th width="591.666748046875">Location (i.e. XY Coordinates)  </th></tr></thead><tbody><tr><td>osgb1000002017442067</td><td>317125.257, 668211.235</td></tr><tr><td>osgb1000000396384131</td><td>190481.79, 232279.2</td></tr><tr><td>osgb1000002051913976</td><td>449509.85, 505435.69</td></tr><tr><td>osgb1000000288748397</td><td>218600.34, 959309.68</td></tr><tr><td>osgb5000005336944433</td><td>261011.67, 193349.099</td></tr><tr><td>osgb1000002036654488</td><td>364563.28, 526860.35</td></tr></tbody></table>

## Discrepancies <a href="#hlk115182660" id="hlk115182660"></a>

In this release 35 errors were detected, of which, 21 have existed since the previous refresh. These are all considered to be minor errors and there are no major errors present.

We aim to have all errors resolved prior to the next release as part of ongoing quality improvements.

## Next release

The next release of OS MasterMap Topography Layer is scheduled for **16 February 2026.**&#x20;


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