# Intermittent 429 RESOURCE\_EXHAUSTED despite low quota usage (billing enabled)

**URL:** <https://discuss.ai.google.dev/t/intermittent-429-resource-exhausted-despite-low-quota-usage-billing-enabled/115831>\
**Category:** Gemini API\
**Tags:** vertexai\
**Created:** [January 16, 2026, 1:12pm UTC](https://discuss.ai.google.dev/t/intermittent-429-resource-exhausted-despite-low-quota-usage-billing-enabled/115831 "2026-01-16T13:12:13Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![cas\_stg](https://d1dlmcr85iqnpo.cloudfront.net/user_avatar/discuss.ai.google.dev/cas_stg/32/33010_2.png) [@cas\_stg](https://discuss.ai.google.dev/u/cas_stg)\
**Post date:** [January 16, 2026, 1:12pm UTC](https://discuss.ai.google.dev/t/intermittent-429-resource-exhausted-despite-low-quota-usage-billing-enabled/115831/1 "2026-01-16T13:12:13Z")

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Dear Support Team,

We are intermittently experiencing **429 RESOURCE\_EXHAUSTED** errors from the **Gemini / Vertex AI API** in a **paid project** , even though all visible quotas are well within limits.

**Error example:**  
`429 RESOURCE_EXHAUSTED`  
`{`  
` “error”: {`  
` “code”: 429,`  
` “message”: “Resource exhausted. Please try again later.`  
`Please refer to ``https://cloud.google.com/vertex-ai/generative-ai/docs/error-code-429”``,`  
` “status”: “RESOURCE_EXHAUSTED”`  
` }`  
`}`

**Project ID:** `hopeful-breaker-454412-u9`

**Details:**

- Billing is enabled and active

- Visible quota usage in the Cloud Console is consistently \<1%

- Errors occur a few times per hour under normal, steady production load (not very large bursts)

- Retries are implemented with backoff and jitter (base ~3s + 2–5s jitter)

**Impact:**  
This is affecting a production application.

**Request:**  
We suspect an **undocumented internal quota, concurrency limit, token-throughput limit, or shared capacity throttling** that is not exposed in the quota dashboard.

Could you please:

1. Confirm which internal quota or limit is being exceeded

2. Verify the project is not being enforced under free-tier or incorrect backend limits

3. Advise whether concurrency or capacity limits can be adjusted

Screenshots of the quota dashboard are attached.

Thank you for your assistance.

 ![image](https://d3qe71uytubmmx.cloudfront.net/original/3X/e/5/e5a23f5ff77f95e8e60f459586c7b53ec711ec3f.png)

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<div class="post-metadata">

**Author:** ![Organspendeausweis](https://d1dlmcr85iqnpo.cloudfront.net/user_avatar/discuss.ai.google.dev/organspendeausweis/32/22765_2.png) [@Organspendeausweis](https://discuss.ai.google.dev/u/Organspendeausweis)\
**Post date:** [January 18, 2026, 7:59am UTC](https://discuss.ai.google.dev/t/intermittent-429-resource-exhausted-despite-low-quota-usage-billing-enabled/115831/2 "2026-01-18T07:59:08Z")

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We have the same issue. We are on Tier 1 and get error 429, but can not track down the quota that caused it, because nothing shows up in “current usage percentage”.

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**Author:** ![ASHQKING](https://d1dlmcr85iqnpo.cloudfront.net/user_avatar/discuss.ai.google.dev/ashqking/32/69910_2.png) [@ASHQKING](https://discuss.ai.google.dev/u/ASHQKING)\
**Post date:** [January 19, 2026, 4:58am UTC](https://discuss.ai.google.dev/t/intermittent-429-resource-exhausted-despite-low-quota-usage-billing-enabled/115831/3 "2026-01-19T04:58:56Z")

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The `429 RESOURCE_EXHAUSTED` error in this context typically stems from one of three causes that are **not** visible in the “Requests Per Minute” (RPM) view you shared.

### Recommended Troubleshooting Steps

#### Step 1: Verify Token Usage (TPM)

Go back to the **IAM & Admin \> Quotas** page:

1. Filter by the exact model causing errors (e.g., `gemini-2.5-flash`).

2. Look for **“base\_model\_id\_and\_resolution: gemini-2.5-flash…-tokens-per-minute”**.

3. **Check:** Is this bar spiking during your error windows? If so, you need to request a quota increase specifically for **TPM** , not RPM.

#### Step 2: Test a GA Model vs. Preview

If the errors are coming from `gemini-3-flash-preview`:

- **Action:** Temporarily switch that traffic to `gemini-1.5-pro-002` or `gemini-1.5-flash-002` (Stable/GA versions).

- **Why:** GA models have Service Level Agreements (SLAs) and reserved capacity. If the errors stop, the issue was “Preview” capacity throttling, which you cannot fix other than by waiting or switching models.

#### Step 3: Regional Redundancy

If `europe-west4` is legitimately experiencing “Shared Capacity” issues (which happens):

- **Action:** Configure your client to failover to a different region (e.g., `us-central1` or `europe-west1`) upon receiving a 429.

- **Note:** This requires your data residency requirements to allow processing in other regions.

### Summary for your Engineering Team

> **Hypothesis:** The application is likely hitting a **Token Throughput (TPM)** limit which is distinct from the Request (RPM) limit shown, OR it is suffering from **Service Health/Capacity** throttling on the `gemini-3-flash-preview` model.

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<div class="post-metadata">

**Author:** ![cas\_stg](https://d1dlmcr85iqnpo.cloudfront.net/user_avatar/discuss.ai.google.dev/cas_stg/32/33010_2.png) [@cas\_stg](https://discuss.ai.google.dev/u/cas_stg)\
**Post date:** [January 19, 2026, 10:45am UTC](https://discuss.ai.google.dev/t/intermittent-429-resource-exhausted-despite-low-quota-usage-billing-enabled/115831/4 "2026-01-19T10:45:05Z")

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Additional evidence:

 ![image](https://d3qe71uytubmmx.cloudfront.net/original/3X/7/a/7a607de3cd839ec36ee4774b2279e904b9d7f079.png)

We are seeing 429 RESOURCE\_EXHAUSTED errors on `gemini-3-flash-preview` even when token usage is well below 50k TPM and the quota dashboard shows “Unlimited” for this model.

The error responses contain no quota name or dimension.

This strongly suggests shared capacity or preview-model admission control rather than a visible quota limit.

Could you please confirm whether our project is being throttled due to preview model capacity and whether a GA alternative or capacity adjustment is recommended?

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**Author:** ![Mateo\_Hysa](https://d1dlmcr85iqnpo.cloudfront.net/user_avatar/discuss.ai.google.dev/mateo_hysa/32/87049_2.png) [@Mateo\_Hysa](https://discuss.ai.google.dev/u/Mateo_Hysa)\
**Post date:** [January 23, 2026, 4:09pm UTC](https://discuss.ai.google.dev/t/intermittent-429-resource-exhausted-despite-low-quota-usage-billing-enabled/115831/5 "2026-01-23T16:09:56Z")

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Have been experiencing the same thing with other models. I thought Vertex AI was supposed to be the reliable one with a couple steps to set up, but that does not seem to be the case.