There are only 14,094 verses in the BBT published version of Srimad Bhagavatam. The total number of chapters is 335, which tallies with the stated number of chapters for the entire SB, but the number of verses is not 18,000. What is the explanation for the missing 3,906 verses?
Regarding the numbers of chapters in the Bhagavatam (or other literatures), ancient Sanskrit texts were not originally divided into numbered chapters. The word for chapter, adhyaya, literally means a ‘going over’, i.e ‘a unit of study,’ as conceived at a later time. So there may have been different chapter divisions and enumerations done by different communities. This does not mean that there are necessarily missing verses.