How to read your Volton invoice.

Every month you receive a statement and invoices for each service. This page explains when the documents arrive, why there are several of them, and what every line means. The samples are real September documents with names and addresses replaced.

How the settlement works.

  1. Each service is settled separately.

    Open supply is the electricity Volton buys from you and sells to you. Aggregation is what your battery or solar park earns on the balancing and capacity markets. Each service gets its own statement and its own invoices.

  2. The statement comes first.

    A statement is a report, not a demand for payment. It lists revenues (what Volton owes you) and costs (what you owe Volton), with VAT per section. The statement is the basis for the invoices.

  3. Then the invoices are issued.

    A document receives its number only when it is issued. Numbers are consecutive without gaps. VAT is calculated per line and summed. The invoice date is the last day of the settlement period.

  4. Invoices arrive by email.

    You receive an email with a PDF link. If you have something to pay, the email also carries a payment link. If Volton pays you, there is nothing for you to do.

The due date depends on the service: 15 days on an open supply invoice, 30 days on an aggregation invoice. September documents are dated 30.09.2026.

The documents depend on whether you are a private person or a company.

Open supply is always sold by Volton Power Management OÜ. Aggregation is sold by Volton Technology OÜ, but if you also take open supply, everything comes from one seller, Volton Power Management OÜ.

Private person

One invoice per service. No self-billed invoice.

  • The revenues Volton owes you appear on the invoice as "Tasaarveldatud tulud / Revenue offset" and are subtracted after VAT.
  • If the revenues exceed the invoice, the invoice shows "To pay 0.00" and Volton pays the difference out to you.
  • Revenue lines carry no VAT (category O); cost lines carry 24% VAT. That is why the statement shows two balances: excluding and including VAT.
  • The margin is included in the energy price. There are no separate margin lines.

Company (VAT registered)

Two invoices per service.

  • Self-billed invoice (pöördarve): Volton buys from you. The closing line reads "We pay you". The document carries the note KMS §37 lg 5 and your company IBAN.
  • Invoice (arve): Volton sells to you. The closing line reads "To pay" with Volton's IBAN.
  • Every line carries 24% VAT. Margins are on separate lines.
  • The statement's "Result for the period incl. VAT" equals the self-billed invoice minus the invoice.

What every line means.

Lines are grouped per metering point (EIC code) with the metering point address under the code. Quantities are MWh with six decimals. For spot-priced energy the amount is authoritative and the printed unit price is the average (amount divided by quantity), not a tariff.

Open supply lines

  • Elektrienergia müük (börsihind)revenue

    Energy you exported to the grid, valued per 15-minute interval at the spot price.

  • Müügimarginaalcost

    Volton's margin on exported energy, EUR/MWh per your agreement. A separate line for VAT payers only.

  • Elektrienergia ost (börsihind)cost

    Energy you imported from the grid, at spot.

  • Ostumarginaalcost

    Volton's margin on imported energy.

  • Elektrienergia müük / ost (no suffix)revenue or cost

    For a private person the margin is folded into the price: sale = spot minus export margin, purchase = spot plus import margin.

  • Tasakaalustamisvõimsuse tasu (tarbimine / tootmine)cost

    The Elering balancing capacity fee, passed through unchanged per MWh in both directions. 3.73 EUR/MWh in 2026.

  • Monthly fee, imbalance fee, fixed pricecost

    Appear only when your pricing includes a monthly fee, an imbalance fee percent or a fixed price.

Aggregation lines

  • Energiaturu tulu / kulurevenue or cost

    Net of the energy markets: aFRR and mFRR activations, Nord Pool trades and imbalance. A positive net is revenue, a negative net is a cost. Quantity is the regulated MWh.

  • Võimsusturu tulurevenue

    Reserve capacity payments minus penalties. Quantity is the allocated MW summed over the settled hours.

  • Volton teenustasu (10% / 20%)cost

    The service fee percent in your agreement, applied to the net market result: energy revenue plus capacity revenue minus energy cost. Quantity is the days in the period.

Rows below the table

  • Summa / Netsummary

    Sum of the lines before VAT.

  • Käibemaks 24% / VATsummary

    VAT calculated per line and summed.

  • Tasaarveldatud tulud / Revenue offsetsummary

    Private person's invoice only: the statement's revenues (incl. VAT) subtracted from the invoice.

  • Ülekantud eelmisest perioodistsummary

    A balance below 1.00 EUR carried over from the previous document of the same type.

  • Tasuda / To pay · Tasume teile / We pay yousummary

    The closing line. An invoice asks you to pay; a self-billed invoice states what Volton pays.

  • Tasaarvelduse jääk ilma KMsummary

    Statement balance excluding VAT: revenues minus costs.

  • Perioodi tulemus koos KMsummary

    Statement balance including VAT. Plus means Volton owes you, minus means you owe Volton. This is the amount the invoices settle.

Samples from September 2026.

Real documents with names, addresses, metering point codes and bank details replaced. The amounts are unchanged.

Private person: two statements, two invoices

A private person with one metering point who exports solar energy and whose battery takes part in aggregation. Not VAT registered.

Supply statement (09.26-AT)
Supply statement (09.26-AT)

2026-09-0384 · Supply statement (09.26-AT)

The -AT suffix means open supply only. Revenue is exported energy at spot minus 4.00 EUR/MWh, without VAT. Costs are imported energy at spot plus 3.23 EUR/MWh and the Elering fee, all with 24% VAT. The two balances differ because the revenue carries no VAT and the costs do.

Total revenues
80.35
Total costs
−51.66
VAT on costs
−12.40
Balance excl. VAT
28.69
Result for the period incl. VAT
+16.29
Invoice 0366, open supply
Invoice 0366, open supply

0366 · Invoice 0366, open supply

Only the statement's cost lines appear on the invoice. The statement's revenue arrives as the "Revenue offset" row. 64.06 − 80.35 = −16.29. The closing line shows 0.00 and Volton pays 16.29 out to the customer.

Net
51.66
VAT 24%
12.40
Revenue offset
−80.35
To pay
0.00
Aggregation statement (09.26-AGR)
Aggregation statement (09.26-AGR)

2026-09-0667 · Aggregation statement (09.26-AGR)

The -AGR suffix means aggregation only. Service fee check: 20% × (43.76 + 12.40 − 12.43) = 8.75. The fee is charged on the net market result, not on gross revenue.

Energy market revenue
43.76
Capacity market revenue
12.40
Energy market cost
−12.43
Volton service fee (20%)
−8.75
Result for the period incl. VAT
+29.90
Invoice 0822, aggregation
Invoice 0822, aggregation

0822 · Invoice 0822, aggregation

The service fee is printed as 30 days × 0.29167. Volton pays the customer 29.90 for this service. Together with the open supply invoice the customer receives 46.19 for September and pays nothing.

Net
21.18
VAT 24%
5.08
Revenue offset
−56.16
To pay
0.00

Company: two statements, four invoices

A VAT-registered company with one solar park metering point. Sell margin 6.00 and buy margin 3.00 EUR/MWh, aggregation service fee 10%.

Supply statement (09.26-AT)
Supply statement (09.26-AT)

2026-09-0593 · Supply statement (09.26-AT)

For a VAT payer the margins are separate lines and every section carries 24% VAT. The two gross figures are exactly the two invoices that follow: self-billed invoice 0751 for 1 848.88 and invoice 0752 for 1 402.53.

Total revenues
1 491.03
Revenues incl. VAT
1 848.88
Total costs
−1 131.08
Costs incl. VAT
−1 402.53
Result for the period incl. VAT
+446.35
Self-billed invoice 0751, open supply
Self-billed invoice 0751, open supply

0751 · Self-billed invoice 0751, open supply

Volton is the buyer, the company is the seller. Volton issues the document on the company's behalf, which is why it carries the note "Endale arve koostamine – KMS §37 lõige 5" and the company IBAN as beneficiary. The company is paid full spot for its export.

Net
1 491.03
VAT 24%
357.85
We pay you
1 848.88
Invoice 0752, open supply
Invoice 0752, open supply

0752 · Invoice 0752, open supply

The company's cost side in five lines: sell margin, purchase at spot, buy margin and the Elering fee in both directions. The sell margin sits on the invoice, not on the self-billed invoice: the margin is a service and carries VAT.

Net
1 131.08
VAT 24%
271.45
To pay
1 402.53
Aggregation statement (09.26-AGR)
Aggregation statement (09.26-AGR)

2026-09-0789 · Aggregation statement (09.26-AGR)

The park regulated 15.298 MWh in September and held 185.627 MW of reserve capacity summed over the hours. Service fee check: 10% × (2 305.94 + 246.49 − 878.49) = 167.39.

Energy market revenue
2 305.94
Capacity market revenue
246.49
Energy market cost
−878.49
Volton service fee (10%)
−167.39
Result for the period incl. VAT
+1 868.13
Self-billed invoice 0912, aggregation
Self-billed invoice 0912, aggregation

0912 · Self-billed invoice 0912, aggregation

The statement's revenue lines on one self-billed invoice. Numbers 0912 and 0913 are consecutive because the aggregation pair was issued in one run.

Net
2 552.43
VAT 24%
612.59
We pay you
3 165.02
Invoice 0913, aggregation
Invoice 0913, aggregation

0913 · Invoice 0913, aggregation

3 165.02 − 1 296.89 = 1 868.13, the statement's result for the period including VAT. The company pays the invoice and receives the self-billed amount. The two are not netted on the documents.

Net
1 045.88
VAT 24%
251.01
To pay
1 296.89