The firm announced a temporary suspension of its building plans last year following the completion of its £10m store in Chiswick, west London by McLaren Construction.
But George Osborne unveiled plans to impose VAT on the self storage industry last week.
The move would allow Big Yellow to recover the tax on construction costs and claim back VAT on previous work which could help fund three new stores.
Big Yellow said: “The proposed VAT change would see a significant reduction in the cost of construction of new stores given that VAT on the construction costs would be recoverable.
“Furthermore the Group would be entitled to a repayment of previously unrecovered VAT on past construction expenditure, which we believe would be sufficient to fund the £14.3 million construction cost of new stores on the three sites that the Group currently owns at Gypsy Corner and Enfield (both in London), and in central Guildford.”