This is an example of how a hobby can become a business: Read more about hobby or business. 

Ole refurnishes the barn and purchases the necessary equipment. To establish a customer base, he contacts the “Farmer's market” cooperative. He is encouraged to sell his products on market days, and when he takes his flatbreads to the market, they are in great demand.

During the first year, his income is good, even though he was only in full production during the final two months of the year. However, his substantial set-up costs meant that he had a significant deficit during the year. Although he expects production and sales to be considerably higher during the following year, he believes that his venture should not yet be considered taxable activity.
  
He therefore decides to document this year's income and costs by completing form RF-1298 Oppstart av virksomhet - Bilagsoversikt (Starting a business - Summary of vouchers, in Norwegian only) and retain all vouchers.  If his flatbread production proves to generate a profit within five years, he will (with the approval of the tax office) be able to have this year approved as the start-up year and have his tax assessment amended.
 

Year 1: Start of flatbread production

Date	Voucher	Description	Income	Cost
	1	Purchase of oven		25,000
	2	Purchase of materials for barn		10,000
	3	Purchase of miscellaneous equipment		10,000
	4	Ingredients		6,000
	5	Miscellaneous sales	30,000
	6	Electricity, etc.		10,000

Year 2

Ole has an accident and is on sick leave for much of the year. He only manages very limited production and generates a small profit, but he does not give up and he hopes that next year will fulfil his expectations.

After two years of running his business, he realises that the condition that the enterprise is “likely to generate a profit over time” will probably not be met. He does not submit an income statement, but he retains his vouchers and fills in form RF-1298 for this year as well.

Date	Voucher	Description	Income	Cost
	1	Purchase of electricity, etc.		5,000
	2	Purchase of ingredients		7,000
	3	Miscellaneous sales	30,000
	4	Marketing		5,000

Year 3

This year sees growth in both production and sales, and Ole realises that the business is likely to generate a substantial profit. By the year-end, the business has generated gross income of NOK 250,000 and incurred NOK 75,000 in total costs.

Ole realises that he meets the conditions for being considered as running a business. He submits an income statement and transfers the net income from the income statement to his tax return. Together with the income statement, he submits form RF-1298 with an overview of vouchers for each of the two previous start-up years (as shown above).

Only now will the tax office assess whether Ole meets the conditions for running a taxable activity. If so, they will then assess when the activity actually started, and whether there are any grounds for amending the tax assessment for the two start-up years.

If the conditions are met, Ole's tax assessment will be amended for the start-up years that are approved, with the changes to taxable income that the tax office deems relevant following an assessment of the submitted voucher summaries and any dialogue with Ole.