Skip to content
CARTIS
← Return to profile

Cartis diligence evidence schedule

DayOne Lahti Data Center Campus

PRJ-0018 · Site · Lahti / Kiveriö, Finland

Record last updated Oct 28, 2026

Scope and capacity

DayOne began construction of its Kiveriö campus in April 2026. The first building is planned for 50 MW of IT load within a 128 MW potential campus, with TikTok confirmed as principal tenant.

Headline: Not established in published records

Numbers refer to their stated physical boundaries and are not added together. Source dates, claim dates and record updates have different meanings. Missing dates and locators are not inferred.

Claims and exhibit sources

Jump to a claim (19)

Current status · Under construction

Actual · DayOne Lahti Data Center Campus (Project)

Claim 2240 · Recorded claim type: Actual · Review: Approved · Claim date: Not stated

  1. TikTok investoi miljardin Lahden datakeskukseen

    City of Lahti · Document date: Apr 10, 2026 · Corroborating

    Source reference: SRC-0122 · Fact sheet · Recorded authority: Official primary

    Source URL

    https://www.lahti.fi/uutiset/tiktok-investoi-miljardin-lahden-datakeskukseen/

  2. DayOne data center construction to start in Lahti — SRV strengthens its position

    SRV Group · Document date: Apr 7, 2026 · Primary

    Source reference: SRC-0120 · Company announcement · Recorded authority: Party primary

    Source URL

    https://news.cision.com/srv-yhtiot-oyj/r/dayone-data-center-construction-to-start-in-lahti---srv-strengthens-its-position-in-the-growing-mark%2Cc4331404

Site area · 98,901 square metres

Actual · DayOne Lahti Data Center Campus (Project)

Claim 2241 · Recorded claim type: Actual · Review: Approved · Claim date: Aug 14, 2025

  1. DayOne announces flagship hyperscale data center project in Lahti, Finland

    DayOne Data Centers · Document date: Aug 14, 2025 · Primary

    Source reference: SRC-0116 · Company announcement · Recorded authority: Party primary

    Source URL

    https://dayonedc.com/markets/dayone-announces-flagship-hyperscale-data-center-project-in-lahti-finland

Site location · Kiveriö; Ilmarisentie 3 / Väinämöisentie 2a

Actual · DayOne Lahti Data Center Campus (Project)

Claim 2242 · Recorded claim type: Actual · Review: Approved · Claim date: Not stated

  1. DayOne data center construction to start in Lahti — SRV strengthens its position

    SRV Group · Document date: Apr 7, 2026 · Corroborating

    Source reference: SRC-0120 · Company announcement · Recorded authority: Party primary

    Source URL

    https://news.cision.com/srv-yhtiot-oyj/r/dayone-data-center-construction-to-start-in-lahti---srv-strengthens-its-position-in-the-growing-mark%2Cc4331404

  2. Datakeskuksen rakentamislupa rakennus- ja ympäristölupalautakuntaan

    City of Lahti · Document date: Oct 2, 2025 · Corroborating

    Source reference: SRC-0118 · Government record · Recorded authority: Official primary

    Source URL

    https://www.lahti.fi/uutiset/datakeskuksen-rakentamislupa-rakennus-ja-ymparistolupalautakuntaan/

  3. A €1.2 billion data centre to be built in Kiveriö, Lahti

    City of Lahti · Document date: Aug 14, 2025 · Primary

    Source reference: SRC-0117 · Company announcement · Recorded authority: Official primary

    Source URL

    https://www.lahti.fi/en/news/a-e1-2-billion-data-centre-to-be-built-in-kiverio-lahti/

Planned IT capacity · 50 MW IT

Planned / design or future potential · Lahti first 50 MW building (Phase)

Claim 2243 · Recorded claim type: Design · Review: Approved · Claim date: Aug 14, 2025

Headline treatment: Phase scope; not a whole-site figure

  1. TikTok announces additional €1 Billion investment in Finland

    TikTok · Document date: Apr 7, 2026 · Corroborating

    Source reference: SRC-0121 · Company announcement · Recorded authority: Party primary

    Source URL

    https://newsroom.tiktok.com/tiktok-announces-additional-1-billion-investment-in-finland?lang=en-150

  2. DayOne announces flagship hyperscale data center project in Lahti, Finland

    DayOne Data Centers · Document date: Aug 14, 2025 · Primary

    Source reference: SRC-0116 · Company announcement · Recorded authority: Party primary

    Source URL

    https://dayonedc.com/markets/dayone-announces-flagship-hyperscale-data-center-project-in-lahti-finland

Potential IT capacity · 128 MW IT

Planned / design or future potential · Lahti full campus potential (Phase)

Claim 2244 · Recorded claim type: Forecast · Review: Approved · Claim date: Aug 14, 2025

Headline treatment: Phase scope; not a whole-site figure

  1. TikTok announces additional €1 Billion investment in Finland

    TikTok · Document date: Apr 7, 2026 · Corroborating

    Source reference: SRC-0121 · Company announcement · Recorded authority: Party primary

    Source URL

    https://newsroom.tiktok.com/tiktok-announces-additional-1-billion-investment-in-finland?lang=en-150

  2. DayOne announces flagship hyperscale data center project in Lahti, Finland

    DayOne Data Centers · Document date: Aug 14, 2025 · Primary

    Source reference: SRC-0116 · Company announcement · Recorded authority: Party primary

    Source URL

    https://dayonedc.com/markets/dayone-announces-flagship-hyperscale-data-center-project-in-lahti-finland

Permit application floor area · 40,000 square metres

Reported rounded · Lahti permit and site preparation (Phase)

Claim 2245 · Recorded claim type: Reported rounded · Review: Approved · Claim date: Oct 2, 2025

  1. Datakeskuksen rakentamislupa rakennus- ja ympäristölupalautakuntaan

    City of Lahti · Document date: Oct 2, 2025 · Primary

    Source reference: SRC-0118 · Government record · Recorded authority: Official primary

    Source URL

    https://www.lahti.fi/uutiset/datakeskuksen-rakentamislupa-rakennus-ja-ymparistolupalautakuntaan/

Data hall storeys · 2 storeys

Proposal · Lahti permit and site preparation (Phase)

Claim 2246 · Recorded claim type: Proposal · Review: Approved · Claim date: Oct 2, 2025

  1. Datakeskuksen rakentamislupa rakennus- ja ympäristölupalautakuntaan

    City of Lahti · Document date: Oct 2, 2025 · Primary

    Source reference: SRC-0118 · Government record · Recorded authority: Official primary

    Source URL

    https://www.lahti.fi/uutiset/datakeskuksen-rakentamislupa-rakennus-ja-ymparistolupalautakuntaan/

Construction start · Launched immediately after 2026-04-07 contractor announcement

Actual · Lahti first 50 MW building (Phase)

Claim 2247 · Recorded claim type: Actual · Review: Approved · Claim date: Apr 7, 2026

  1. DayOne data center construction to start in Lahti — SRV strengthens its position

    SRV Group · Document date: Apr 7, 2026 · Primary

    Source reference: SRC-0120 · Company announcement · Recorded authority: Party primary

    Source URL

    https://news.cision.com/srv-yhtiot-oyj/r/dayone-data-center-construction-to-start-in-lahti---srv-strengthens-its-position-in-the-growing-mark%2Cc4331404

Ready for service target · 2027

Forecast · Lahti first 50 MW building (Phase)

Claim 2248 · Recorded claim type: Forecast · Review: Approved · Claim date: Aug 14, 2025

  1. DayOne data center construction to start in Lahti — SRV strengthens its position

    SRV Group · Document date: Apr 7, 2026 · Corroborating

    Source reference: SRC-0120 · Company announcement · Recorded authority: Party primary

    Source URL

    https://news.cision.com/srv-yhtiot-oyj/r/dayone-data-center-construction-to-start-in-lahti---srv-strengthens-its-position-in-the-growing-mark%2Cc4331404

  2. DayOne announces flagship hyperscale data center project in Lahti, Finland

    DayOne Data Centers · Document date: Aug 14, 2025 · Primary

    Source reference: SRC-0116 · Company announcement · Recorded authority: Party primary

    Source URL

    https://dayonedc.com/markets/dayone-announces-flagship-hyperscale-data-center-project-in-lahti-finland

Dayone announced investment · €1,200,000,000

Forecast · DayOne Lahti Data Center Campus (Project)

Claim 2249 · Recorded claim type: Forecast · Review: Approved · Claim date: Aug 14, 2025

  1. DayOne announces flagship hyperscale data center project in Lahti, Finland

    DayOne Data Centers · Document date: Aug 14, 2025 · Primary

    Source reference: SRC-0116 · Company announcement · Recorded authority: Party primary

    Source URL

    https://dayonedc.com/markets/dayone-announces-flagship-hyperscale-data-center-project-in-lahti-finland

  2. A €1.2 billion data centre to be built in Kiveriö, Lahti

    City of Lahti · Document date: Aug 14, 2025 · Corroborating

    Source reference: SRC-0117 · Company announcement · Recorded authority: Official primary

    Source URL

    https://www.lahti.fi/en/news/a-e1-2-billion-data-centre-to-be-built-in-kiverio-lahti/

Principal tenant · TikTok

Actual · DayOne Lahti Data Center Campus (Project)

Claim 2251 · Recorded claim type: Actual · Review: Approved · Claim date: Apr 7, 2026

  1. TikTok investoi miljardin Lahden datakeskukseen

    City of Lahti · Document date: Apr 10, 2026 · Corroborating

    Source reference: SRC-0122 · Fact sheet · Recorded authority: Official primary

    Source URL

    https://www.lahti.fi/uutiset/tiktok-investoi-miljardin-lahden-datakeskukseen/

  2. TikTok announces additional €1 Billion investment in Finland

    TikTok · Document date: Apr 7, 2026 · Primary

    Source reference: SRC-0121 · Company announcement · Recorded authority: Party primary

    Source URL

    https://newsroom.tiktok.com/tiktok-announces-additional-1-billion-investment-in-finland?lang=en-150

Tiktok announced investment · €1,000,000,000

Transaction scope · DayOne Lahti Data Center Campus (Project)

Claim 2252 · Recorded claim type: Transaction scope · Review: Approved · Claim date: Apr 7, 2026

  1. TikTok investoi miljardin Lahden datakeskukseen

    City of Lahti · Document date: Apr 10, 2026 · Corroborating

    Source reference: SRC-0122 · Fact sheet · Recorded authority: Official primary

    Source URL

    https://www.lahti.fi/uutiset/tiktok-investoi-miljardin-lahden-datakeskukseen/

  2. TikTok announces additional €1 Billion investment in Finland

    TikTok · Document date: Apr 7, 2026 · Primary

    Source reference: SRC-0121 · Company announcement · Recorded authority: Party primary

    Source URL

    https://newsroom.tiktok.com/tiktok-announces-additional-1-billion-investment-in-finland?lang=en-150

Power connection agreement · Executed with Lahti Energy

Actual · DayOne Lahti Data Center Campus (Project)

Claim 2253 · Recorded claim type: Actual · Review: Approved · Claim date: Aug 14, 2025

  1. DayOne announces flagship hyperscale data center project in Lahti, Finland

    DayOne Data Centers · Document date: Aug 14, 2025 · Primary

    Source reference: SRC-0116 · Company announcement · Recorded authority: Party primary

    Source URL

    https://dayonedc.com/markets/dayone-announces-flagship-hyperscale-data-center-project-in-lahti-finland

Grid connection contract value · €38,000,000

Transaction scope · DayOne Lahti Data Center Campus (Project)

Claim 2254 · Recorded claim type: Transaction scope · Review: Approved · Claim date: Sep 12, 2025

  1. Eltel to build grid connections for DayOne's Data Center — contract value EUR 38 million

    Eltel Group · Document date: Sep 12, 2025 · Primary

    Source reference: SRC-0119 · Company announcement · Recorded authority: Party primary

    Source URL

    https://www.eltelgroup.com/en/eltel-to-build-grid-connections-for-dayones-data-center-contract-value-eur-38-million/

Grid connection completion target · 2027 Q1

Forecast · DayOne Lahti Data Center Campus (Project)

Claim 2255 · Recorded claim type: Forecast · Review: Approved · Claim date: Sep 12, 2025

  1. Eltel to build grid connections for DayOne's Data Center — contract value EUR 38 million

    Eltel Group · Document date: Sep 12, 2025 · Primary

    Source reference: SRC-0119 · Company announcement · Recorded authority: Party primary

    Source URL

    https://www.eltelgroup.com/en/eltel-to-build-grid-connections-for-dayones-data-center-contract-value-eur-38-million/

Cooling design · Air cooled chiller; no freshwater cooling

Design · DayOne Lahti Data Center Campus (Project)

Claim 2256 · Recorded claim type: Design · Review: Approved · Claim date: Aug 14, 2025

  1. DayOne announces flagship hyperscale data center project in Lahti, Finland

    DayOne Data Centers · Document date: Aug 14, 2025 · Primary

    Source reference: SRC-0116 · Company announcement · Recorded authority: Party primary

    Source URL

    https://dayonedc.com/markets/dayone-announces-flagship-hyperscale-data-center-project-in-lahti-finland

Waste heat reuse · Under exploration with local partners

Design · DayOne Lahti Data Center Campus (Project)

Claim 2257 · Recorded claim type: Design · Review: Approved · Claim date: Aug 14, 2025

  1. DayOne announces flagship hyperscale data center project in Lahti, Finland

    DayOne Data Centers · Document date: Aug 14, 2025 · Primary

    Source reference: SRC-0116 · Company announcement · Recorded authority: Party primary

    Source URL

    https://dayonedc.com/markets/dayone-announces-flagship-hyperscale-data-center-project-in-lahti-finland

  2. A €1.2 billion data centre to be built in Kiveriö, Lahti

    City of Lahti · Document date: Aug 14, 2025 · Corroborating

    Source reference: SRC-0117 · Company announcement · Recorded authority: Official primary

    Source URL

    https://www.lahti.fi/en/news/a-e1-2-billion-data-centre-to-be-built-in-kiverio-lahti/

Projected operational jobs · 100 jobs

Forecast · DayOne Lahti Data Center Campus (Project)

Claim 2258 · Recorded claim type: Forecast · Review: Approved · Claim date: Aug 14, 2025

  1. DayOne announces flagship hyperscale data center project in Lahti, Finland

    DayOne Data Centers · Document date: Aug 14, 2025 · Primary

    Source reference: SRC-0116 · Company announcement · Recorded authority: Party primary

    Source URL

    https://dayonedc.com/markets/dayone-announces-flagship-hyperscale-data-center-project-in-lahti-finland

Peak construction workers · 1,000 workers

Forecast · DayOne Lahti Data Center Campus (Project)

Claim 2259 · Recorded claim type: Forecast · Review: Approved · Claim date: Aug 14, 2025

  1. DayOne announces flagship hyperscale data center project in Lahti, Finland

    DayOne Data Centers · Document date: Aug 14, 2025 · Primary

    Source reference: SRC-0116 · Company announcement · Recorded authority: Party primary

    Source URL

    https://dayonedc.com/markets/dayone-announces-flagship-hyperscale-data-center-project-in-lahti-finland

Counterparties and capital

City of Lahti · Government authority · CMP-0073

DayOne Data Centers · Operator · CMP-0071

Eltel Networks · Contractor · CMP-0077

Kiinteistö Oy Lahden Ilmarisentie 3 · Owner · CMP-0075

Lahti Energy · Utility provider · CMP-0074

SRV Group Plc · Contractor · CMP-0076

TikTok · Tenant · CMP-0072

Investment commitment

€1,200,000,000 · Aug 14, 2025

DayOne aggregate project estimate; no financing sources or spend schedule disclosed.

DayOne Data Centers (Sponsor)

Sources (2)

Financing record 16; claim-specific source links appear in the exhibit sources where published.

Investment commitment

€1,000,000,000 · Apr 7, 2026

TikTok investment/customer scope; not additive to DayOne's project estimate and not site financing.

TikTok (Sponsor)

Sources (2)

Financing record 17; claim-specific source links appear in the exhibit sources where published.

This schedule captures public Cartis research. It is not a title, lien or legal-opinion report. Document page/section locators and claim review timestamps are included only when published; this version has no separate locator or claim-review-time feed.