LONDON (Reuters Breakingviews) - Rishi Sunak’s procrastination may yield some unexpected benefits. Britain’s finance minister has delayed a decision on whether to introduce a new 2% online sales levy that would have hit companies like Amazon.com. This buys time for more joined-up thinking on how best to adapt the tax system to the rise of internet shopping. Sunak may increase corporate tax at his March 3 budget to finance extensions to economic support measures, The Sunday Times reported on Feb. 21. An internet sales levy on pure-play online businesses might have generated extra tax revenues but would not have done much to dent the budget deficit, which the Office for Budget Responsibility expects will rise to 394 billion pounds in the financial year ending in April. Take Amazon, which would pay the lion’s share of the new tax. A 2% levy applied to its 2020 UK revenue would more than double its total UK tax bill but still only raise 669 million pounds. If it were applied to fast fashion companies Asos and Boohoo’s 2020 sales, they would pay an extra 65 million pounds and nearly 25 million pounds respectively. Grocers and other high-street retailers complain that business rates, a levy on the value of company’s property, unfairly penalise retailers that have shops and not just warehouses in suburban locations. But a finance minister who has to plug a yawning budget deficit may struggle to significantly cut property taxes without finding alternative sources of tax receipts since these rates raise nearly 60% as much as the 50 billion pounds that the Sunak gets in corporation tax. He may therefore want to think more creatively about online sales. Many retailers that have bricks and mortar shops are selling more wares online. Applying the 2% internet sales levy to more than just pure-play online retailers would be even better for the government’s coffers. For example, Nielsen says online revenues for grocers account for an average of 16% of sales. On this basis, if the 2% tax were applied to the internet sales of listed supermarkets Tesco, J Sainsbury and WM Morrison Supermarkets, Sunak would raise an extra 330 million pounds, according to a Breakingviews calculation. Updating the UK system to deal with 21st century companies takes time and will be tricky but would lead to a bigger tax haul. BREAKINGVIEWS Reuters Breakingviews is the world"s leading source of agenda-setting financial insight. As the Reuters brand for financial commentary, we dissect the big business and economic stories as they break around the world every day. A global team of about 30 correspondents in New York, London, Hong Kong and other major cities provides expert analysis in real time.