The English Rugby Football Union invested a record £99.6m into the game while suffering a £6m operating loss in 2016-17.
The national governing body published its annual report and accounts on Thursday.
The financial results showed lower year-on-year revenues, but that can be attributed to England hosting the 2015 Rugby World Cup, with those figures reported in last year's accounts.
There was £228m of Rugby World Cup revenue in 2015-16. The 2016-17 revenue of £184.9m was 20 per cent greater than the last season with the same match profile (2012-13) and excluding any World Cup impact.
Investment in rugby was up £9.8m (11 per cent) on 2015-16, bringing the total investment in the five years of the strategic plan cycle to £408m, up by £55m (16 per cent).
RFU chief executive Steve Brown said: "This was always going to be a period of reinvigoration and I am glad to say that a comparison with the last season with the same match profile and unaffected by the Rugby World Cup 2015 revenues, shows total revenue up by 20 per cent.
"Growth was achieved across the key revenue streams, and our overheads were nine per cent lower year on year."
Growth was attributed to: ticketing (up 87 per cent), with 1.1m seats sold for 17 matches at Twickenham; broadcasting (up three per cent) and merchandising and licensing (up 27 per cent).
Ticket revenues (excluding World Cup games) increased by £17.6m (87 per cent) as Twickenham hosted seven games - three Six Nations internationals plus four autumn Tests - as opposed to two Six Nations games and two World Cup warm-up matches.
The East Stand at Twickenham is being refurbished to add hospitality space and boost finances.
A growth in capital of £22.1m comes following the sale of £28.2m in debentures, including the corporate hospitality facilities being constructed in the East Stand.
The RFU reported a £63.7m investment in Professional Rugby, up by 14 per cent, including year one of both the eight-year Professional Game Agreement and four-year players deal.
The balance sheet shows net assets of £215m, with profit and loss reserves of £18.5m.
The RFU also pointed to a sixth successive year of increased investment in rugby development and its commitment to investment in facilities, including artificial grass pitches.