Read on 2026-10-16. The page quotes 2023 figures; check the current base before you rely on any amount.
Registration must come first
Plataforma ONE says that being registered with Social Security on the day of starting the activity is a requirement. It adds that if you report your registration after beginning to work, it will be considered that the registration date is the first day of the month, and you will not be eligible for fee discounts. It also says that you may face a fine ranging from €3,750 to €12,000 depending on the severity, and you will have to pay the corresponding contributions from the date the authorities become aware of the start of your activity. The same page says that if you have already started working on your own account, you must also communicate the registration, but it will be considered late for all purposes.
The contribution base for the late period
- If you requested your registration outside the deadline, from the day you started the activity until the last day of the month in which you reported it, the contribution base for this period will be the minimum base of level 1 in the general table, which in 2023 is €950.98 per month.
- The contributions for the late period will not be included in the annual regularization of contributions.
- If the Labor Inspection or the General Treasury of Social Security registered you at their request, the contribution base from the registration date to the last day of the month before the effective date is the minimum base of level 1, and they may set a higher base.
Choosing your dates
- You can register and deregister as many times as you want, although you can only choose the registration and deregistration dates three times a year.
- You can only choose the registration and deregistration dates three times a year, and you must have requested them within the specified timeframe.
- The other registrations processed during the year take effect on the first day of the month in which you commence your activity.
The safe order is: get the NIE, ask for the registration, then invoice. The full procedure is in the autónomo guide.
Source
Checked on 2026-10-16 against Plataforma ONE: Registration of individual entrepreneurs (self-employed). Rules and fees change, so read the official page again before you pay or travel.