No opening date has been announced for Terafab — but the tax agreements signed in 2026 encode a schedule anyway. Grimes County's abatement runs from 2027 to 2036, the project is structured in four phases, and analysts put first meaningful output no earlier than mid-2028. At 100 million square feet, it would be the largest building ever constructed.

⚡ TL;DR — Quick Answer

👉 The reframe that beats every other article: stop asking when Terafab "opens." It is a four-phase build with staggered incentives. Phases will come online years apart — there is no single opening day.

When Will Terafab Open? The Honest Answer

Neither Tesla nor SpaceX has published a completion date, a first-wafer date, or a formal groundbreaking date for the Grimes County complex. The August 6, 2026 announcement confirmed the site and a $16.8 billion first phase without attaching a schedule to either.

What has been said publicly is vaguer: civil work beginning almost immediately, with full construction expected within months. That is a direction, not a date.

The closest thing to a professional estimate came from Morgan Stanley in March 2026, which projected first output no earlier than mid-2028. Independent analysis has been more conservative still, suggesting it will likely be the 2030s before Terafab produces chips on process technology it developed itself.

Treat any specific "Terafab opening date" you see online as fabricated. As of August 10, 2026 no such date exists in any filing, press release or government announcement.

The Timeline Hidden in the Tax Agreements

Here is what almost no coverage does: read the incentive paperwork. Tax agreements have dates in them, and those dates reveal what the parties actually expect.

The county deal: a dated 10-year window

Grimes County approved a 100% property tax abatement running for ten years, from 2027 through 2036, alongside a payment-in-lieu-of-taxes arrangement. Tom's Hardware reported the PILOT structure as a $10 million lump sum followed by $20 million annually across a 35-year term.

Two inferences follow. First, an abatement beginning in 2027 implies taxable improvements were expected on the ground by then — consistent with construction starting in late 2026. Second, a 35-year payment schedule signals the parties are planning around a multi-decade operating life, not a quick build.

The school deals: four phases, four agreements

The JETI application was structured in four phases, with Iola ISD and Anderson-Shiro CISD each voting 5–2 to approve all four on July 14, 2026. Each phase carries its own 10-year school property tax reduction.

The school districts' incentives total roughly $1.66 billion. Four separately negotiated phases with independent 10-year clocks is not how you structure a single facility opening on a single date — it is how you structure a build-out spanning a decade or more.

The approval sequence, which had a hard deadline

  • June 15, 2026 — the Texas Comptroller approved all eight JETI applications, opening a 30-day decision window.
  • July 14, 2026 — Iola ISD and Anderson-Shiro CISD both approved all four phase agreements, 5–2.
  • July 15, 2026 — the deadline for Governor Abbott's decision; without it the deal would have collapsed regardless of the school votes.
  • August 6, 2026 — the site, the $16.8 billion first phase and 3,000 permanent jobs were announced publicly.

💡 Unique insight: the phase structure is the timeline. Ten-year clocks per phase, an abatement window opening in 2027, and a 35-year payment term together describe a project measured in decades — which is why no one has published a single opening date.

Terafab Size: 100 Million Square Feet in Context

The facility is planned at more than 100 million square feet of floor space, in a structure renderings show running roughly 2.5 miles end to end. There is no completed building on Earth at that scale.

BuildingApproximate floor areaTerafab multiple
Terafab (planned)100,000,000 sq ft
Giga Texas, Austin10,000,000 sq ft~10x smaller
The Pentagon6,600,000 sq ft~15x smaller
Apple Park2,820,000 sq ft~35x smaller
SpaceX Gigasat factory11,000,000 sq ft~9x smaller

Tom's Hardware published a visualisation comparing the footprint against Giga Texas, the Pentagon, Apple Park and the Mall of America combined. CoStar framed it more simply as roughly fifteen Pentagons, dropped into a county of about 30,000 people some 30 miles east of Texas A&M.

Size in money, not square feet

Perspective: even the full $119 billion build-out is a small fraction of what independent analysts say the stated terawatt goal would cost. The size headline and the capacity headline do not describe the same project.

What Is Actually Under Construction Right Now

Only the Austin research fab — formally the Advanced Technology Chip Fabrication facility, or ATCF — at the North Campus of Giga Texas. Ground was broken there in April 2026, and it is a roughly $3 billion project supporting a few thousand wafers per month.

Progress is unusually well documented because drone observers fly the site regularly. Recent flyovers show the main foundation taking a defined rectangular shape and extending southward, with GeoPier ground-improvement columns being driven into softer soil sections and construction materials stockpiling.

A quieter signal from late July 2026 matters more than the concrete: four new permits were filed for the contractor trailer complex and temporary Tesla offices — the kind of fit-out infrastructure that appears when a project is preparing for equipment installation rather than still planning.

Do not conflate the two sites. Drone footage of active construction is the Austin ATCF, not Grimes County. Coverage frequently blurs this, making the production complex look further along than it is.

The Four Phases: What Is Known

PhaseWhat is documentedWhat is not
Phase 1$16.8B capital investment; 3,000 permanent jobs; JETI agreement approved July 2026Start date, completion date, first-wafer date
Phase 2JETI agreement approved with its own 10-year school tax clockScope, cost, trigger conditions
Phase 3JETI agreement approvedScope, cost, timing
Phase 4JETI agreement approved; total across phases referenced at up to ~$119BEverything else

SpaceX has stated that 60% to 80% of the 3,000 permanent roles would go to residents of Grimes and neighbouring Brazos County — a commitment that only makes sense across a hiring ramp measured in years, not a single opening.

What Different Sources Imply About Timing

SourceImplied timingFor what
Grimes County abatement window2027–2036Taxable operations expected to begin in this period
Morgan Stanley (March 2026)Mid-2028 at the earliestFirst meaningful chip output
Independent process analysis2030sChips on Terafab's own process technology
JETI phase structureFour 10-year clocksFull build-out spanning well beyond a decade
PILOT agreement term35 yearsPlanned operating life of the campus
Company statementsCivil work immediately; construction within monthsSite preparation only

Read together, these do not conflict — they describe a staged project where site work begins in 2026, the first taxable improvements appear around 2027, first chips arrive at the earliest in 2028, and full capability lands sometime in the 2030s.

Checklist: Milestones That Would Confirm the Schedule

  • Construction permits filed in Grimes County — the first hard evidence that vertical construction has begun.
  • A published groundbreaking date for the production complex. Still absent as of August 2026.
  • Cleanroom shell completion at the Austin ATCF, which precedes any equipment installation.
  • Lithography tool orders, given multi-year lead times — the single best predictor of a real production date.
  • Phase 2 activation, which would show the phased structure is being executed rather than merely permitted.
  • Hiring ramps for fab process engineers in the Brazos Valley, which typically begin 18–24 months before production.

👉 Best single indicator: the county publishes its executed agreements and public-information records. Permit filings move months before press releases do.

FAQ

When will Terafab be completed?

No completion date has been announced. The four-phase structure and 10-year tax clocks imply full build-out extends well into the 2030s.

When will Terafab start producing chips?

No first-wafer date exists. Morgan Stanley projected first meaningful output no earlier than mid-2028; independent analysis suggests the 2030s for chips made on Terafab's own process technology.

How big is Terafab in square feet?

More than 100 million square feet planned — around ten times Giga Texas and roughly fifteen times the Pentagon, in a building about 2.5 miles long.

Has Terafab construction started?

At the Austin research fab, yes — foundation work is actively progressing. At the Grimes County production complex, only civil work and site preparation have been described; no groundbreaking has been announced.

How many phases does Terafab have?

Four. Each phase has its own JETI tax agreement with an independent 10-year school property tax reduction, all approved in July 2026.

Summary

Terafab has no opening date because it was never designed to have one. It is a four-phase build with staggered 10-year incentive clocks, a county abatement window running 2027 to 2036, and a 35-year payment agreement — the paperwork of a project measured in decades.

The size figure is real and unprecedented: over 100 million square feet, larger than any building ever completed. The construction that exists today is the Austin research fab, where foundations are visibly progressing and contractor fit-out permits are already being filed.

The gap between those two facts — a documented decade-scale schedule versus a single visible foundation — is the most accurate picture of where Terafab stands in August 2026.

Tracking the build for investment, contracting or job reasons? County permit filings and lithography tool orders will reveal the real timeline long before any announcement does — bookmark this page for updates as phases activate.

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